The ISA's Research Committee on the Sociology of Law and the Government of the Basque Country established the International Institute for the Sociology of Law in Oñati, Gipuzkoa, Spain in 1988. From the outset, the Institute created academic links and collaborative relations with various European and non-European universities by providing facilities for seminars, workshops, visiting scholars and library research. The Institute has as a result grown into an important base for the global network of scholars who work on law and social science issues.

The Institute is headed by a rotating Scientific Director, the senior academic administrator (André-Jean Arnaud, 1989-91; Paavo Uusitalo, 1991-92; Rogelio Pérez Perdomo, 1992-93; Roberto Bergalli, 1993-95; Johannes Feest, 1995-97; Jacek Kurczewski, 1997-98; Pierre Guibentif, 1998-00; William Felstiner, 2000- 2002; Manuel Calvo-García, 2002-2003; Volkmar Gessner, 2003-2005). The Scientific Director becomes a visiting professor of the Universidad del País Vasco and, aided by various Board committees, oversees the teaching and workshop programmes, the development of the library, relations with Basque universities and the Institute's publications. The Administrative and Financial Director is Mr. José Antonio Goyenaga.

A major activity of the Institute is its yearlong course leading to an MA degree in the sociology of law. The course now includes 20-25 students annually from about a dozen countries in Europe, Africa and North, Central and South America. To date, students have come from thirty-eight countries. Faculty members, who each provide two weeks of instruction in their special areas of interest, have come from twenty-six different countries.

The Institute's socio-legal library, one of the most extensive in Europe, contains major collections in English and Spanish and significant materials in French, German and Italian. It expects in the near future to expand its collections in other directions, especially in non-Western languages. Internet access to the library catalogue is free of charge. The Institute provides free accommodations to a number of scholars each year who come to Onati to carry out library research.

The Institute is housed in a Spanish Renaissance building completed in 1543 as a university law school. The building, donated by the provincial government of Gipuzkoa, has been renovated to accommodate the library, administrative offices, rooms for meetings and classes and a video centre. This building is situated in the heart of old Oñati, a short walking distance from another which provides accommodations for students, teachers and those who attend workshops at the Institute. This 18th century residence, the Palacio Antía, made available by the town of Onati, has also recently been renovated and provides commons rooms for social activities as well as comfortable, modern accommodations.