Professional involvement, memberships
| 1969 - 1970 | Secretary, Research Planning Commission, Max-Planck-Institute for Educational Research, Berlin, Germany |
| 1975 - present | Member of the Research Council, German Association for Asian Studies (Deutsche Gesellschaft für Asienkunde) |
| 1991 - 2000 | Chairman Research Council Japan-Korea, German Association for Asian Studies (Deutsche Gesellschaft für Asienkunde) |
| 1976 | Fulbright Fellowship for Study Visits of Educational Experts to the U.S.: study on admission to higher education in the U.S.A., commissioned by the International Council for Educational Development |
| 1977 - 1985 | Member of various advisory committees of the Education and Science Union (Gewerkschaft Erziehung und Wissenschaft) |
| 1979 - 1981 | Member, Commission on Teaching in Higher Education, German Research Association (Senatskommission für Hochschuldidaktik der Deutschen Forschungsgemeinschaft) |
| 1980 - 1984 | Chairman, Working Group on Higher Education, Section of Sociology of Education, German Sociological Association (Deutsche Gesellschaft für Soziologie) |
| 1980 - 1993 | Member, Selection Commission, German Academic Exchange Service (Deutscher Akademischer Austauschdienst) |
| 1981 - 1985 | Member of the Advisory Board for Higher Education of the State of Bremen (Hochschulbeirat Bremen) |
| 1982 - 1984 | Consultant, Regional Institute for Higher Education and Development, Singapore |
| 1982 - 1990 | Member of the Board, European Institute of Education and Social Policy, Paris, |
| 1983 - 1991 | Member of Advisory Board, Hochschulausbildung (Journal) |
| 1984 - 1987 | Member of Advisory Board, American Journal of Education |
| 1984 - 1989 | Coordinator, German-French Commission for the Promotion of Research on Higher Education |
| 1984 - 1992 | Foreign Research Fellow, Center for European Studies, Graduate School and University Center, City University of New York |
| 1984 - 1993 | Member of the Board, Education Centre, German Adult Education Society (Pädagogische Arbeitsstelle des Deutschen Volkshoch- schulverbandes) |
| 1986 - present | Vice-president, Society for Research into Higher Education (United Kingdom) |
| 1988 - 1996 | Member of Advisory Board, Educational Policy |
| 1988 - 1997 | Member of Board, Association of Social Science-Oriented Japanese Studies (Vereinigung für sozialwissenschaftliche Japanforschung) |
| 1988 - 1994 | Chairman, Association of Social Science-Oriented Japanese Studies (Vereinigung für sozialwissenschaftliche Japanforschung) |
| 1988 - 1998 | Member of the Steering Group, Consortium of Higher Education Researchers (CHER) |
| 1988 - 1989 | Secretary, Consortium of Higher Education Researchers (CHER) |
| 1992 - 1998 | Chairman, Consortium of Higher Education Researchers (CHER) |
| 1989 - 1990 | OECD Reviewer of Education Policy in the Netherlands |
| 1989 | Visiting Fellow, Center for the Study of Higher Education, University of California, Berkeley |
| 1989 - present | Member of Advisory Board, Studies in Higher Education |
| 1990 - 1993 | Member of Steering Committee, CRE-Columbus Project (of Latin American and European universities) |
| 1990 - present | Co-Editor, Higher Education |
| 1990 - 1993 | Member of the Advisory Council, Nucleo de Pesquisas sobre Ensine Superior, Universidade de Sao Paulo |
| 1990 - 1991 | Member, Berlin Science Commission (Berliner Wissenschafts- kommission) |
| 1991 - 1992 | Member, State Higher Education Commission of Sachsen-Anhalt (Landeshochschulstrukturkommission Sachsen-Anhalt) |
| 1991 - 1996 | Member of the Advisory Board, Research Group on Higher Education, Berlin-Karlshorst (Projektgruppe Hochschulforschung) |
| 1991 - 2000 | Member of Editorial Board, Asien |
| 1991 - present | Member of Editorial Board, Das Hochschulwesen |
| 1991 - 2000 | Member of Editorial Board, European Journal of Education |
| 1992 - 1997, 2000 | Chairman of Editorial Board, European Journal of Education |
| 1997 - 1999 | Co-editor, European Journal of Education |
| 1991 - 2000 | Coordinator of the research consortium "Relationships between Education and Employment Systems in Japan from a Comparative Perspective" |
| 1992 | OECD Reviewer of Educational Policy in Sweden |
| 1992 - present | Honorary Member, Academy of Humanities and Sciences of the City University of New York, U.S. |
| 1992 - 1995 | Member, State Adult Education Commission, Bremen (Strukturkommission Weiterbildung des Senats der Freien Hansestadt Bremen) |
| 1992 - present | Member, Academia Europaea |
| 1996 - 1996 | Member of the Education Committee of the Academia Europaea |
| 1993 - 1996 | Associate Member, International Academy of Education |
| 1997 - present | Member, International Academy of Education |
| 1998 - present | Member of the Board, International Academy of Education |
| 1993 - present | Regular Member, International Higher Education Academy of Sciences, Moscow |
| 1994 | OECD Reviewer of Educational Policy in Finland |
| 1995 - present | Member of the Board of Advisors, South African Journal of Higher Education |
| 1995 - present | Member of the Editorial Board, Tertiary Education and Management |
| 1995 - 2006 | Consultant, Association of African Universities |
| 1997 - 1998 | Honorary guest, National Institute for Educational Research, Tokyo, Japan |
| 1997 - present | Member of the Advisory Board, Journal of Studies in International Education |
| 1997 - present | President, EAIR |
| 1998 - 2001 | Coordinator of the research consortium "Higher Education and Graduate Employment in Europe" |