In Portugal, the university system has a strong theoretical basis and is highly research-oriented while the polytechnical system provides a more practical training and is profession-oriented. Degrees in fields such as medicine, law, pharmaceutical sciences, natural sciences, economics, psychology or veterinary medicine are taught only in university institutions. Other fields like engineering, technology, management, education, agriculture, sports, or humanities are taught both in university and polytechnic institutions. Specifically vocationally oriented degrees such as, nursing, health care technician, accounting technician, preschool and primary school teaching, are only offered by the polytechnic institutions.
The oldest university is the University of Coimbra founded in 1290. The largest university, by number of enrolled students, is the University of Porto - with approximately 28,000 students. The Catholic University of Portugal, the oldest non-state-run university (concordatary status), was instituted by decree of the Holy See and has been recognized by the State of Portugal since 1971. A few polytechnical higher education institutions, though formed as such in the 1980s, have their origin in 19th century educational institutions - this is the case of the Instituto Superior de Engenharia de Lisboa, the Instituto Superior de Engenharia do Porto and the Escola Superior Agrária de Coimbra.
Public or private higher education institutions or courses cannot operate, or are not accredited, if they are not recognized by the Ministério da Ciência, Tecnologia e Ensino Superior (Ministry of Science, Technology and Higher Education). The two systems of higher education - university and polytechnic - are linked, and it is possible to transfer from one to the other through extraordinary effort. It is also possible to transfer from a private institution to a public one (or vice versa) on the same basis.
Many universities are usually organized by faculty (faculdade). Institute (instituto) and school (escola) are also common designations for autonomous units of Portuguese higher learning institutions, and are always used in the polytechnical system, though several universities also use these systems.
Access to public higher education institutions is subject to enrollment restrictions (numerus clausus), and students must compete for admission. Students who hold a diploma of secondary education (12th grade) or the equivalent, who meet all legal requirements, particularly exams in specific subjects in which minimum marks must be obtained, may apply. Any citizen over 23 years old who does not have the secondary education diploma (12th grade) can attempt to gain admission to a limited number of vacant places available, through special examination which includes an interview (Decree law: Decreto-Lei 64/2006, de 21 de Março). Public university's tuition fees are greater than polytechnics', and polytechnic weekend and evening classes are usually organized. For a large number of academic fields, undergraduate and graduate admission criteria and student evaluation in most public university institutions are usually more selective and demanding than in many private institutions or polytechnic institutions.
Access to private higher education institutions is regulated by each institution. After 2006, with the approval of new legislation on the frame of the Bologna Process, any polytechnic or university institution of Portugal is able to award a first cycle of study, known as licenciatura (licentiate) plus a second cycle which confers a mestrado (master's degree). Before then, only university institutions awarded master's degrees. All institutions award master's degrees after a second cycle of study, and some universities award integrated master's degrees (joint degrees) through a longer single cycle of study, with fields such as medicine having an initial 6-year study cycle needed for a master's degree. Doutoramentos (Ph.D. degrees) are only awarded by university institutions. Only university institutions carry out fundamental research in addition to research and development. However, since after the Bologna Process (2006/2007) an increasingly large number of polytechnical institutions have established to some extent their own research and development units.
There are also special higher education institutions linked with the military and the police. These institutions generally have good reputations and are popular among students because their courses are a passport to the military/police career. These state-run institutions are the Air Force Academy, the Military Academy, the Naval School and the Instituto Superior de Ciências Policiais e Segurança Interna.
According to the OECD's Programme for International Student Assessment (PISA), the average Portuguese 15-year-old student was for many years underrated and underachieving in terms of reading literacy, mathematics and science knowledge in the OECD, nearly tied with the Italian and just above those from countries like Greece, Turkey and Mexico. However, since 2010, PISA results for Portuguese students improved dramatically. If this was true, it could be translated into a higher average level of readiness and academic skill among freshmen attending Portuguese universities and other higher education institutions. However, the Portuguese Ministry of Education announced a 2010 report published by its office for educational evaluation GAVE (Gabinete de Avaliação do Ministério da Educação) which criticized the results of PISA 2009 report and claimed that the average Portuguese teenage student had profund handicaps in terms of expression, communication and logic, as well as a low performance when asked to solve problems. They also claimed that those fallacies are not exclusive of Portugal but indeed occur in other countries due to the way PISA was designed.