Doctor of Philosophy, abbreviated Ph.D. or PhD for the Latin Latin: philosophiæ doctor, meaning "teacher of philosophy", (or, more rarely, D.Phil., for the equivalent Latin: doctor philosophiæ) is an advanced academic degree awarded by universities. In many, but not all countries in the English-speaking world, it has become the highest degree one can earn (but see also the higher doctorates awarded by universities in the UK, Ireland and some Commonwealth countries) and applies to graduates in a wide array of disciplines in the sciences and humanities. The Ph.D. has become a requirement for a career as a university professor or researcher in most fields.
The detailed requirements for award of a Ph.D. degree vary throughout the world; however, there are a number of common factors. In some countries (the US, Canada, Denmark, for example), most universities require coursework for Ph.D. degrees. In many other countries (especially those with a greater degree of specialization at the undergraduate level, such as the UK) there is no such condition in general. It is not uncommon, however, for individual universities or departments to specify analogous requirements for students not already in possession of a master's degree.
In countries requiring coursework, there is usually a prescribed minimum amount of study — typically two to three years full time, or a set number of credit hours — which must take place before submission of a thesis. This requirement is usually waived for academic staff submitting a portfolio of peer-reviewed published work. The candidate may also be required to successfully complete a certain number of additional, advanced courses relevant to his or her area of specialization.
A candidate must submit a thesis or dissertation consisting of a suitable body of original academic research, which is in principle worthy of publication in a peer-refereed context. In many countries a candidate must defend this work before a panel of expert examiners appointed by the university; in other countries, the dissertation is examined by a panel of expert examiners who stipulate whether the dissertation is in principle passable and the issues that need to be addressed before the dissertation can be passed.
The origins of the doctorate dates back to the ijazat attadris wa 'l-iftta ("license to teach and issue legal opinions") in the medieval Madrasahs from the 9th century, though it was limited to Islamic law at the time, as in a Doctor of Laws degree. The doctorate was later extended to philosophy in the European universities in the Middle Ages which generally placed all academic disciplines outside the professional fields of theology, medicine and law under the broad heading of "philosophy" (or "natural philosophy" when referring to science). The degree of Doctor of Philosophy was a doctorate, generally granted as honorary degrees to select and well-established scholars.
According to Wellington, Bathmaker, Hung, MucCullough and Sikes (2005), the first Ph.D. degree was awarded in Paris in 1150, but not until the early nineteenth century did the term "Ph.D. degree" acquire its modern meaning as the highest academic doctoral degree, thanks to university practice in Germany. As Wellington et al. explain, prior to the nineteenth century professional doctoral degrees could only be awarded in theology (Th.D.), law (J.D.), or medicine (M.D.). In 1861, Yale University adopted the German practice (first introduced in the 19th century at the Friedrich Wilhelm University in Berlin) of granting the degree to younger students who had completed a prescribed course of graduate study and successfully defended a thesis/dissertation containing original research in science or in the humanities.
From the United States the degree spread to Canada in 1900, and then to the United Kingdom in 1917. This displaced the existing Doctor of Philosophy degree in some universities; for instance, the D.Phil. (higher doctorate in the faculty of philosophy) at the University of St Andrews was discontinued and replaced with the Ph.D. (research doctorate). Oxford retained the D.Phil. abbreviation for their research degrees. Some newer UK universities, for example Buckingham (est. 1976), Sussex (est. 1961), and, until a few years ago, York (est. 1963), chose to adopt the D.Phil., as did some universities in New Zealand.
Ph.D. degrees are awarded under different circumstances and with different requirements in many different countries.
Admission to a Ph.D. program within Australia and New Zealand requires the prospective student to have completed a bachelor's degree with an honours component or a higher degree, such as a post graduate master's degree by research or a master's degree by course work.
In most disciplines, honours require an extra year of study including a large research component in addition to coursework; however, in some disciplines such as engineering, law and pharmacy, honours are automatically awarded to high achievers of the normal four-year program. To obtain a Ph.D. position, students must usually gain first class honours, but may sometimes be admitted with high second class honours (known as a 2A, or Second Class Honours Division I). Alternatively, a student who fails to achieve first or second class Honours may apply for a research masters course (usually 12–18 months) and upgrade to a Ph.D. program after the first year, pending sufficient improvement.
In both Australia and New Zealand, Ph.D. students are sometimes offered a scholarship to study for their Ph.D. degree. The most common of these in Australia is the government-funded Australian Postgraduate Award (APA), which provides a living stipend to students of approximately AU$ 20,000 a year (tax free). Most universities in both countries also offer a similar scholarship that matches the APA amount, but are funded by the university. In recent years, with the tightening of research funding in Australia, these scholarships have become increasingly hard to obtain. Due to a continual increase to living costs, many Ph.D. students are forced to live under the poverty line, . In addition to the more common APA and University scholarships, Australian and New Zealand students also have other sources of funding in their Ph.D. degree. These could include, but are not limited to, scholarships offered by schools, research centres and commercial enterprise. For the latter, the amount is determined between the university and the organisation, but is quite often set at the APA (Industry) rate, roughly AU$7,000 more than the usual APA rate. Australian and New Zealand students are often also able to tutor undergraduate classes and do guest lectures (much like a teaching assistant in the USA) to generate income. An Australian or New Zealand Ph.D. scholarship is paid for a duration of 3 years, while a 6 month extension is usually possible upon citing delays out of the control of the student.
Australian-citizen and other eligible Ph.D. and Research Masters students in Australia are not charged course fees as these are paid for by the Australian Government under the Research Training Scheme. International students and Coursework Masters students must pay course fees, unless they receive a scholarship to cover them. In order to attract top international doctoral students, the New Zealand government reduced international doctoral fees to the domestic fee level in 2006.
See also: Education in Argentina.
In the Latin American docta, the admission to a Ph.D. program at an Argentine University requires the full completion of a Master's degree or a Licentiate's degree. Non-Argentinian Master's titles are generally accepted into a Ph.D. program when the degree comes from a recognized university.
While a significant portion of postgraduate students finance their tuition and living costs with teaching or research work at private and state-run institutions, international institutions, such as the Fullbright Program and the Organization of American States (OAS), have been known to grant full scholarships for tuition with apportions for housing.
Upon completion of at least two years' research and course work as a graduate student, a candidate must demonstrate truthful and original contributions to his or her specific field of knowledge within a frame of academic excellence. The doctoral candidate's work should be presented in a dissertation or thesis prepared under the supervision of a tutor or director, and reviewed by a Doctoral Committee. This Committee should be composed of examiners external to the program, and at least one of them should also be external to the institution. The academic degree of Doctor — abbreviated, "Dr.", with a suffix appropriate to the specific field — is received after a successful defense of the candidate’s dissertation.
Admission to a Ph.D. program at a Canadian university may require completion of a Master's degree in a related field, with sufficiently high grades and proven research ability. In some cases, a student may progress directly from an Honours Bachelor's degree to a Ph.D. program. The student usually submits an application package including a research proposal, letters of reference, transcripts, and in some cases, a sample of the student's writing. A common criterion for prospective Ph.D students is the comprehensive or qualifying examination, a process that often commences in the second year of a graduate program. Generally, successful completion of the qualifying exam permits continuance in the graduate program. Formats for this examination include oral examination by the student's faculty committee (or a separate qualifying committee), or written tests designed to demonstrate the student's knowledge in a specialized area (see below).
At English-speaking universities, a student may also be required to demonstrate English language abilities, usually by achieving an acceptable score on a standard examination (e.g., Test of English as a Foreign Language (TOEFL)). Depending on the field, the student may also be required to demonstrate ability in one or more additional languages. A prospective student applying to French-speaking universities may also have to demonstrate some English language ability.
While some students work outside the university (or at student jobs within the university), in some programs students are advised (or must agree) not to devote more than ten hours per week to activities (i.e., employment) outside of their studies.
At some Canadian universities, most Ph.D. students receive an award equivalent to the tuition amount for the first four years (this is sometimes called a tuition deferral or tuition waiver). Other sources of funding include teaching assistantships and research assistantships; experience as a teaching assistant is encouraged but not requisite in many programs. Some programs may require all Ph.D. candidates to teach, which may be done under the supervision of their supervisor or regular faculty.
In general, the first two years of study are devoted to completion of coursework and the comprehensive examinations. At this stage, the student is known as a "Ph.D. student." It is usually expected that the student will have completed most of his or her required coursework by the end of this stage. Furthermore, it is usually required that by the end of eighteen to thirty-six months after the first registration, the student will have successfully completed the comprehensive exams.
Upon successful completion of the comprehensive exams, the student becomes known as a "Ph.D. candidate." From this stage on, the bulk of the student's time will be devoted to his or her own research, culminating in the completion of a Ph.D. thesis or dissertation. The final requirement is an oral defense of the thesis, which is open to the public.
At most Canadian universities, the time needed to complete a Ph.D. degree typically ranges from four to six years. It is, however, not uncommon for students to be unable to complete all the requirements within six years, particularly given that funding packages often support students for only two to four years; many departments will allow program extensions at the discretion of the thesis supervisor and/or department chair. Alternate arrangements exist whereby a student is allowed to let their registration in the program lapse at the end of six years and re-register once the thesis is completed in draft form. The general rule is that graduate students are obligated to pay tuition until the initial thesis submission has been received by the thesis office. In other words, if a Ph.D. student defers or delays the initial submission of their thesis they remain obligated to pay fees until such time that the thesis has been received in good standing.
Due to the differences in French education systems in comparison to anglophone systems, students who want to earn the Ph.D. degree must complete a Master of Science program which lasts for 2 years after graduation with a Bachelor's degree (5 years in total).
In France, the Masters program is divided into two branches, Master of Engineering which orients the students towards the working world. On the other hand, a Master of Science orients the students towards research.The Ph.D admission is adopted by a graduate school (in French, "école doctorale"), a Ph.D Student has to follow some courses offered by the graduate school while continuing his/her research at laboratory. His/her research may be carried out in a laboratory, at a university, or in a company. In the last case, the company hires the student as an engineer and the student is supervised by both the company's tutor and a labs' professor. The validation of the Ph.D degree requires generally 3 to 4 years after the Master degree. Consequently, the Ph.D degree is considered in France as a "Bac +8" diploma ."Bac" stands for "Baccalauréat" which is the French High-school diploma.
The financing of Ph.D studies comes mainly from funds for research of French Ministry of National Education. These grants often depend of the results and the student's file. However, the student can apply for funds from a company who can host him/her at its premise (as in the case where Ph.D students do their research in a company). Other resources come from some regional/city projects, some associations, etc.
See also: Education in Germany.
In Germany a Master, Diplom, Magister or Staatsexamen (state examination) degree is usually required to gain admission to a doctoral program. Sometimes good grades or a degree in a related field are additional requirements. The candidate must also find a tenured professor or Privatdozent to serve as the formal advisor on the Dissertation throughout the doctoral program. This advisor is informally termed Doktorvater.
Doctoral programs in Germany generally take three to five years to complete, strongly depending on the subject. Since there are usually no formal classes, and the doctoral candidate mainly conducts independent research under the tutelage of a single professor, a good deal of doctoral candidates work as teaching or research assistants, and are paid a reasonably competitive salary. This is a considerable difference from the situation in many other countries (such as the U. S.) where doctoral candidates are often referred to as Ph.D. "students"; whereas with German candidates, this rather inaccurate term should be avoided.
In early university history the Doctorate was awarded as a first degree. It has since evolved into a research degree.
In German-speaking countries, most Eastern European countries, the former Soviet Union, most parts of Africa, Asia, and many Spanish-speaking countries the corresponding degree is simply called "doctor" and is distinguished by subject area with a Latin suffix (e.g. "Dr.med." for Latin: doctor medicinæ, which is a title like a master, unlike a PhD, "Dr.rer.nat" for Latin: doctor rerum naturalium — Doctor of Science, "Dr. phil." for Latin: doctor philosophiæ, "Dr. iur." for Latin: doctor iuris, which is not equal to a J.D., etc.).
See main article: Dr. philos. (Norwegian degree).
Norway was one of the first countries to introduce the Doctor of Philosophy degree, inspired by the German university system. The degree doctor philosophiae, abbreviated dr. philos., was first awarded in 1847 . The degree was used for all other fields than theology, law and medicine, which had separate degrees: doctor theologiae, doctor juris and doctor medicinae. In the late 20th century new degrees were created in the fields of natural sciences, humanities and social sciences, but it was still possible to obtain the dr. philos. degree in any field. As the dr. philos. degree was one of the four original doctoral degrees and much older than the specific degrees in natural sciences, humanities and social sciences, it was considered more prestigious by some. Both the dr. philos. degree and the other degrees required four years of high-level scientific research which significantly contributed to new knowledge of its field. Most people who started at a doctoral degree had already studied for five or seven years and obtained a Candidate degree (five years) or a Magister degree (seven years).
Following a reform in 2003, all the traditional degrees except dr. philos. were abolished, and replaced by a new doctor of philosophy degree, spelled philosophiae doctor and abbreviated ph.d. The scientific standard of the ph.d. degree is lower, as it in most cases only requires three years of research.
The traditional degree dr. philos., equivalent of four years of scientific research, is still awarded to those who qualify for such a degree without being admitted to an organized doctoral programme.
In principle, a university is free to admit anyone to a Ph.D. programme; however, in practice, admission is usually conditional on the prospective student having successfully completed an undergraduate degree with at least upper second-class honours, or a postgraduate master's degree.
In addition, Ph.D. students from countries outside the EU/EFTA area are required to comply with the Academic Technology Approval Scheme (ATAS), which involves undergoing a security clearance process with the Foreign Office for certain courses in medicine, mathematics and many natural, engineering and material sciences.  This requirement was introduced in 2007 due to concerns about terrorism and weapons proliferation.
In the United Kingdom, funding for Ph.D. students is sometimes provided by government-funded Research Councils or the European Social Fund, usually in the form of a tax-free bursary which consists of tuition fees together with a stipend of around GBP 12,940 per year for three years (rising to £14,940 per year in London) , whether or not the degree continues for longer. Research Council funding is sometimes 'earmarked' for a particular department or research group, who then allocate it to a chosen student, although in doing so they are generally expected to abide by the usual minimum entry requirements (typically a first degree with upper second class honours, although successful completion of a postgraduate master's degree is usually counted as raising the class of the first degree by one division for these purposes). However, the availability of funding in many disciplines (especially humanities, social studies, and pure science subjects) means that in practice only those with the best research proposals, references and backgrounds are likely to be awarded a studentship. The ESRC (Economic and Social Science Research Council) explicitly state that a 2.1 minimum (or 2.2 plus additional masters degree) is required - no additional marks are given for students with a first class honours or a distinction at masters level.
Since 2002, there has been a move by research councils to fund interdisciplinary doctoral training centres such as MOAC which concentrate on communication between traditional disciplines and an emphasis on transferable skills in addition to research training.
Many students who are not in receipt of external funding may choose to undertake the degree part time, thus reducing the tuition fees, as well as creating free time in which to earn money for subsistence.
Students may also take part in tutoring, work as research assistants, or (occasionally) deliver lectures, at a rate of typically £25–30 per hour, either to supplement existing low income or as a sole means of funding.
Funding typically lasts for three or four years for PhD students and four years for students earning both their master's degree and PhD degree; there is a usually first-year assessment to remain in the programme and the thesis is submitted at the end of the 3-4 year program. These periods are usually extended pro rata for part-time students. With special dispensation, the final date for the thesis can be extended for up to four additional years, for a total of seven, but it is rare for students to spend more than four years in the programme. Since the early 1990s, the UK funding councils have adopted a policy of penalising departments where large proportions of students fail to submit their theses in four years (or pro rata equivalent) by reducing the number of funded places in subsequent years.
In the United Kingdom Ph.D. degrees are distinct from other doctorates, most notably the higher doctorates such as D.Litt. (Doctor of Letters) or D.Sc. (Doctor of Science), which are granted on the recommendation of a committee of examiners on the basis of a substantial portfolio of submitted (and usually published) research.
Recent years have seen the introduction of professional doctorates, most notably in the fields of engineering (Eng.D.), education (Ed.D.), clinical psychology (D.Clin.Psych.),public administration (D.P.A.), business administration (D.B.A.), and music (D.M.A.). These typically have a more formal taught component consisting of smaller research projects, as well as a 40,000-60,000 word thesis component, which collectively is equivalent to that of a Ph.D. degree.
In the United States, the Ph.D. degree is the highest academic degree awarded by universities in most fields of study. The Ph.D. degree is often misunderstood to be synonymous with the term doctorate. While the Ph.D. degree is the most common doctorate, the term doctorate can refer to any number of doctoral degrees in the United States. The U.S. Department of Education and the National Science Foundation recognize numerous doctoral degrees as "equivalent", and do not discriminate between them.
American students typically undergo a series of three phases in the course of their work toward the Ph.D. degree. The first phase consists of coursework in the student's field of study and requires one to three years to complete. This often is followed by a preliminary, a comprehensive examination, or a series of cumulative examinations where the emphasis is on breadth rather than depth of knowledge. Some Ph.D. programs require the candidate to successfully complete requirements in pedagogy (taking courses on higher level teaching and teaching undergraduate courses) or applied science (e.g., clinical practica and predoctoral clinical internship in Ph.D. programs in clinical or counseling psychology).
Another two to four years are usually required for the composition of a substantial and original contribution to human knowledge in the form of a written dissertation, which in the social sciences and humanities typically ranges from 50 to 450 pages in length. In many cases, depending on the discipline, a dissertation consists of (i) a comprehensive literature review, (ii) an outline of methodology, and (iii) several chapters of scientific, social, historical, philosophical, or literary analysis. Typically, upon completion, the candidate undergoes an oral examination, sometimes public, by his or her supervisory committee with expertise in the given discipline.
As the Ph.D. degree is often a preliminary step toward a career as a professor, throughout the whole period of study and dissertation research the student may be required or at least offered the opportunity, depending on the university and degree, to teach undergraduate or sometimes graduate courses in relevant subjects.
There are 282 universities in the United States that award the Ph.D. degree, and those universities vary widely in their criteria for admission, as well as the rigor of their academic programs. Typically, Ph.D. programs require applicants to have a Bachelor's degree in a relevant field (and, in rare cases, a master's degree), reasonably high grades, several letters of recommendation, relevant academic coursework, a cogent statement of interest in the field of study, and satisfactory performance on a graduate-level exam specified by the respective program (e.g., GRE, GMAT  ). Specific admissions criteria differ substantially according to university admissions policies and fields of study; some programs in well-regarded research universities (i.e., Research 1 universities) may admit less than five percent of applicants and require an exceptional performance on the GRE along with near-perfect grades, strong support in letters of recommendation, substantial research experience, and academically sophisticated samples of their writing.
As applicants to many Ph.D. programs are not required to have master's degrees, many programs award a Master of Arts or Master of Science degree "in passing" or "in course" based on the graduate work done in the course of achieving the Ph.D. Students who receive such master's degrees are usually required to complete a certain amount of coursework and a master's thesis. Depending on the specific program, masters-in-passing degrees can be either mandatory or optional. Not all Ph.D. students choose to complete the additional requirements necessary for the M.A. or M.S. if such requirements are not mandated by their programs. Those students will simply obtain the Ph.D. degree at the end of their graduate study.
Some programs also include a Master of Philosophy degree as part of the Ph.D. program. The M.Phil., in those universities that offer it, is usually awarded after the appropriate M.A. or M.S. (as above) is awarded, and the degree candidate has completed all further requirements for the Ph.D. degree (which may include additional language requirements, course credits, teaching experiences, and comprehensive exams) aside from the writing and defense of the dissertation itself. This formalizes the "all but dissertation" (ABD) status used informally by some students, and represents that the student has achieved a higher level of scholarship than the M.A./M.S. would indicate - as such, the M.Phil. is sometimes a helpful credential for those applying for teaching or research posts while completing their dissertation work for the Ph.D. degree itself. 
Depending on the specific field of study, completion of a Ph.D. program usually takes four to eight years of study after the Bachelor's Degree; those students who begin a Ph.D. program with a master's degree may complete their Ph.D. degree a year or two sooner. As Ph.D. programs typically lack the formal structure of undergraduate education, there are significant individual differences in the time taken to complete the degree. Many U.S. universities have set a ten-year limit for students in Ph.D. programs, or refuse to consider graduate credit older than ten years as counting towards a Ph.D. degree. Similarly, students may be required to re-take the comprehensive exam if they do not defend their dissertations within five years of taking it. Overall, 57% of students who begin a Ph.D. program in the US will complete their degree within ten years, approximately 30% will drop out or be dismissed, and the remaining 13% of students will continue on past ten years.
Doctoral students are usually discouraged from engaging in external employment during the course of their graduate training. As a result, Ph.D. students at U.S. universities typically receive a tuition waiver and some form of annual stipend. The source and amount of funding varies from field to field and university to university. Many U.S. graduate students work as teaching assistants or research assistants while they are doctoral students. Graduate schools increasingly encourage their students to seek outside funding; many are supported by fellowships they obtain for themselves or by their advisers' research grants from government agencies such as the National Science Foundation and the National Institutes of Health. Many Ivy League and other well-endowed universities provide funding for the entire duration of the degree program (if it is short) or for most of it.
A Ph.D. Candidate (sometimes called Candidate of Philosophy) is a postgraduate student at the doctoral level who has successfully satisfied the requirements for doctoral studies, except for the final thesis or dissertation. As such, a Ph.D. Candidate is sometimes called an "ABD" (All But Dissertation). Although a minor distinction in postgraduate study, achieving Ph.D Candidacy is not without benefit. For example, Ph.D. Candidate status may coincide with an increase in the student's monthly stipend and may make the student eligible for additional employment opportunities.
At some universities, there may be training for those wishing to supervise Ph.D. studies. There is now a lot of literature published for academics who wish to do this, such as Delamont, Atkinson and Parry (1997). Indeed, Dinham and Scott (2001) have argued that the worldwide growth in research students has been matched by increase in a number of what they term "how-to" texts for both students and supervisors, citing examples such as Pugh and Phillips (1987). These authors report empirical data on the benefits that Ph.D. students may gain if they publish their work, and note that Ph.D. students are more likely to do this with adequate encouragement from their supervisors.
Wisker (2005) has noticed how research into this field has distinguished between two models of supervision:The technical-rationality model of supervision, emphasising technique;The negotiated order model, being less mechanistic and emphasising fluid and dynamic change in the Ph.D. process.These two models were first distinguished by Acker, Hill and Black (1994; cited in Wisker, 2005). Considerable literature exists on the expectations that supervisors may have of their students (Phillips & Pugh, 1987) and the expectations that students may have of their supervisors (Phillips & Pugh, 1987; Wilkinson, 2005) in the course of Ph.D. supervision. Similar expectations are implied by the Quality Assurance Agency's Code for Supervision (Quality Assurance Agency, 1999; cited in Wilkinson, 2005).
International Ph.D. Equivalent Degrees:
Ph.D. in popular culture: