"Ph.D." redirects here, for other uses see Ph.D. (disambiguation).
Doctor of Philosophy, abbreviated Ph.D. (American English) or PhD (British English) for the Latin Philosophiæ Doctor, meaning "teacher of philosophy", (or, more rarely, D.Phil., for the equivalent Doctor Philosophiæ) is an advanced academic degree. In the English-speaking world it has become the most common denomination for a research doctorate 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, NGOs, or in the private sector.

History of the Ph.D.
Ph.D.s are awarded under different circumstances and with different requirements in many different English-speaking countries.

Doctor of philosophy degrees across the globe

Australia
Admission to a Ph.D. program within Australia and New Zealand requires the prospective student to have at least completed either a Bachelor's Degree with an Honours component or a higher degree such as a post graduate Master Degree by research or a Master Degree by course work.
In most disciplines, Honours involves 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 PhD after the first year, pending sufficient improvement.

Admission
In Australia, Ph.D. students are sometimes offered a scholarship to study their Ph.D. The most common of these is the Australian Postgraduate Award (APA) scholarship, which provides a living stipend to students of approximately AU$20,000 a year (tax free). Most universities 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. In addition to the more common APA and University scholarships, Australian students also have other sources of funding in their Ph.D. 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 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 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. Completion of a Ph.D. is results dependent, and often students are unable to finish during the tenure of the scholarship.
PhD 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.

Funding

Canada
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 many 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 (below)
At English-speaking universities, students may also be required to demonstrate English language ability, usually via 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 language(s). Prospective students applying to French-speaking universities may also have to demonstrate at least some English language ability.

Admission
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 twelve hours per week to activities 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.
Besides these sources of funding, there are also various competitive scholarships, bursaries, and awards available, such as those offered by NSERC, CIHR, or SSHRC.

Funding
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, and is usually required that by the end of eighteen - 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 thesis defence 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 as the thesis as been received in good standing.

Requirements for completion

France
Engineering schools students passed their "High school + 5 years" studies with a "diplôme d'ingénieur". University Students had to choose previously between a research career Diplôme d'études approfondies (DEA) and a practical one (DESS) in the determination of their "High school + 5 years" degree (BAC+5), both equivalents to the Master's degree. The new European Bologna process will combine these three diplomas into one Master's degree. Admission to a Doctorat programme at a French university normally requires completion of one of these four diplomas in a related field, with sufficiently high grades. The student must usually submit an application package including a research proposal, transcripts, and a sample of the student's writing, i.e. his/her license and masters' theses.
Foreign students may also be required to demonstrate French language ability, usually via an acceptable score on a standard examination, as well for English.

Admission
Grants are usually defined for 3 years. There are different sources of grants and fellowships.
The main source is public, managed by the related universities. A high level of discrimination between topics and disciplines exists between social and technical sciences: a geography DEA preparation class receives only one 3-year scholarship for 60 candidates when a biomolecular science class receives one for 2 candidates. A private company funded program, the "CIFRE" was created for about 10 years. In this programme a company makes an agreement with a candidate for the 3-year Doctorat to be completed. It supports many management and technology Doctorat candidates. However, there is some controversy about the reliability of the results of such a thesis due to confidentiality problems.
While some students work outside the university (or at student jobs within the university), in some programmes students are advised (or must agree) not to devote more than twelve hours per week to activities outside of their studies. However, teaching assistantships are still not common in French universities.
Besides these sources of funding there are also various scholarships, bursaries and awards available.

Funding
In general, there are no exams or qualifiers to pass during the three years of study. The final requirement is a public thesis defence. The minimum amount of time needed to complete a Doctorat is two years, and the maximum is six.

Requirements for completion
See also: Education in Germany

Germany
In Germany a Master, Diploma, 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 to serve as the formal advisor on the Dissertation throughout the doctoral program. This advisor is informally termed Doktorvater ('father of the doctor', for a male professor) or Doktormutter ('mother of the doctor', for a female professor).

Admission
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." — doctor medicinæ — which is not equal to an M.D., "Dr.rer.nat" — doctor rerum naturalium (Doctor of Science), "Dr. phil." — doctor philosophiæ etc.).

History
The dottorato di ricerca (doctorate of research) is the highest Italian academic degree, the equivalent of a Ph.D. The dottorato is a relatively recent addition to the Italian academic landscape, having been instituted in 1980.
Until recent times, no title matching the Bachelor degree existed in the Italian education system and the laurea (the equivalent of a Master's degree) was granted after a single educational program of four, five or six years, including a final research thesis work. Nowadays, with the new system that introduced the Bachelor degree (laurea triennale), a Master's degree (laurea specialistica or laurea magistrale) is required to enter doctoral studies.
Students are admitted to the doctoral program via public concourses offered by individual universities, which set their own standards for admission. The program is from three to five years in length. Because of the relatively recent introduction of the dottorato, the term dottore is officially used in Italy to refer to any person with a university degree: today, even a person with just a Bachelor-equivalent "laurea triennale" use the title "dottore". Therefore, holders of the dottorato acquire the title of dottore di ricerca ("doctor of research").

Italy

United Kingdom
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.

Admission
In the UK, funding for Ph.D. students is often provided by government-funded Research Councils or the ESF. The funding usually takes the form of a tax-free bursary which consists of tuition fees together with a stipend of around GBP12,600 per year for three years (rising to £14,300 per year in London), whether or not the degree continues for longer. Research Council funding is typically allocated to an academic department which then allocate it to students, although restrictions as to the minimum acceptable qualifications are normally specified. These minimum requirements are 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.
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 £15-20 per hour, either to supplement existing income or as a sole means of funding.

Funding
Funding usually lasts for three years full-time (this period is usually extended pro rata for part-time students) and the thesis must usually be submitted within seven years. Since the early 1990s, the UK funding councils have adopted a policy of penalising the departments of students who fail to submit their theses in four years (or equivalent) by reducing the number of funded places in subsequent years.

Completion
In the United Kingdom Ph.D.s 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 vocational doctorates, most notably in the fields of engineering (Eng. D.), education (Ed. D.), clinical psychology (D. Clin. Psychol.) and business administration (D.B.A.). These typically have a more formal taught component, as well as a research component roughly equivalent to that of a Ph.D. This research component typically takes the form of a portfolio of two or three smaller research studies, rather than a single dissertation focusing on one larger academic project.

Other doctorates

United States
In the United States, the Ph.D. is the highest academic degree awarded by universities in many fields of study. US students undergo a series of three phases in the course of their doctoral work: 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.
Another two to four years is usually required for the composition of a substantial and original contribution to human knowledge embodied in a written dissertation that in the social sciences and humanities is typically 100 to 450 pages in length. Dissertations generally 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.
In most research fields, a doctoral degree is required for employment. In some fields, notably the sciences, newly-graduated Ph.D.s are unlikely to obtain a tenure-track post and so undertake one or more postdoctoral positions. However, in recent years, in light of large-scale faculty retirement in North American universities and colleges, the government believes academic employment prospects for freshly minted Ph.D. graduates may be improving., and this is also supported by the Bureau of Labor Statistics, which finds that many of the jobs becoming available for Ph.D.s are part time.
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 (e.g., Doctor of Arts (D.A.), Doctor of Musical Arts (D.M.A.), Doctor of Education (Ed. D.), Doctor of Science (D.Sc.), Doctor of Theology (Th. D.), Doctor of Business Administration (D.B.A.).
See Doctoral Degree in the United States

Overview
Admission to a Ph.D. program in the United States typically requires applicants to have a Bachelor's degree in a relevant field, reasonably high grades, several letters of recommendation, relevant academic coursework, a cogent statement of interest in the field of study, and a satisfactory performance on the Graduate Record Exam (GRE). The general GRE is usually required; an appropriate GRE subject test may also be required. Specific admissions criteria differ substantially according to university admissions policies and fields of study; some programs in well-regarded research universities may admit less than 5% 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.

Admission
As applicants to many Ph.D. programs are not required to have Master's Degrees, many programs award a M.A. or M.S. degree "in passing" or "in course." These degrees are awarded based on graduate work, but are not "terminal" degrees because the recipient is expected to continue his or her education toward 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. at the end of their graduate study.

Master's degree "in passing"
Depending on the specific field of study, completion of a Ph.D. program usually takes between four and eight years of enrollment after the Bachelor's Degree; those students who begin a Ph.D. program with a Master's Degree may complete their Ph.D. a year or two sooner.

See also