Doctor of Philosophy, abbreviated Ph.D. or PhD for the Latin Philosophiæ Doctor, meaning "teacher of philosophy", (or, more rarely, D.Phil., for the equivalent 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 many fields. In addition, many Ph.D. graduates go on to careers in government departments, non-governmental organizations (NGOs), or in the private sector.
The detailed requirements for award of a Ph.D. vary throughout the world; however, there are a number of common factors. 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. There is usually a prescribed minimum period of study — typically two to three years full time — which must take place before submission of the 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. In some countries (the US, Canada, Denmark, for example), most universities require coursework for Ph.D. degrees. In many other countries (especially those which have 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. Universities in the non-English-speaking world have begun adopting similar standards to those of the Anglophone Ph.D. for their research doctorates (see, for example, Bologna Process).
According to Wellington, Bathmaker, Hung, MucCullough and Sikes (2005), the first Ph.D. was awarded in Paris in 1150, but not until the early nineteenth century did the term "Ph.D." 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.
In most disciplines, Honours requires 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 is automatically awarded to high achievers of the normal four-year program. To obtain a Ph.D. position, students must usually gain a First Class Honours, but may sometimes be admitted with a high Second Class Honours (known as a 2A, or Second Class Honours Division I). Alternatively, a student who fails to achieve a First or Second Class Honours may apply for a Research Masters course (usually 12–18 months) and upgrade to a Ph.D. after the first year, pending sufficient improvement.
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.
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.
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 defence of the thesis, which is open to the public.
At most Canadian universities, the time needed to complete a Ph.D. 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.
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.
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. Because there usually are no formal classes, but instead independent research is conducted 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 doctor medicinæ, which is a scientifical title unlike an M.D., "Dr.rer.nat" for doctor rerum naturalium — Doctor of Science, "Dr. phil." for doctor philosophiæ, "Dr. iur." for doctor iuris, which is not equal to a J.D., etc.).
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.
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 US$25–30 per hour, either to supplement existing low income or as a sole means of funding.
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.), 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.
In the United States, the Ph.D. is the highest academic degree awarded by universities in many fields of study. American students typically undergo a series of three phases in the course of their doctoral work, after they have obtained a bachelor's degree. In some cases a master's degree may be required for a Ph.D. program, but in other cases (when a master's is not required) it may not be possible to fully transfer credits from a previously attended master's program to the Ph.D. program. In some fields, the master's is considered terminal, and a university's Ph.D. program may refuse to accept any graduates from the same school's master's program. 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 or comprehensive examination and/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 complete successfully requirements in pedagogy (taking courses on higher level teaching and teaching undergraduate courses) and/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 is typically 50 to 450 pages in length. In many cases, depending on the discipline, a dissertation would consist 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. 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.
The Ph.D. is often misunderstood to be synonymous with the term "doctorate". While the Ph.D. 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. (See Doctoral Degree in the United States).
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. (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. itself.
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).