Dr. Herman Slaats was born in Waalwijk, the Netherlands in 1943. He studied law at the Uni-versity of Nijmegen, and obtained his master's degree in Dutch Law in 1971. Since 1976 he is lecturer in Anthropology of Law at the Faculty of Law of the University of Nijmegen.

Dr. Karen Portier was born in Surabaya. Indonesia, in 1948. She studied Cultural and Social Anthropology at the University of Nijmegen, and obtained her master's degree in Social Science in 1973. She was appointed as a research assistant at the Faculty of Law University Nijmegen in 1979-80, and at the State University of Leiden from 1980 till 1983. She is a member of the scientific staff of the Departement of Agrarian law. Agricultural University Wageningen since 1990.

After their marriage (1971), they conducted legal anthropological research in Karo village society of North Sumatra between 1973 and 1978 as research fellows of the Netherlands Foundation for the Advancement of Research (WOTRO) and of the Program of Indonesian Studies (PRIS). They obtained their Ph.D. in Law on a combined study of the Karo Batak system of rights in land, inheritance and decision-making in 1981. Since then they have been involved in the study of law in urban society in Indonesia, in particular amongst Karo migrants.