Practice Research has evolved as a fruitful research paradigm in Information Systems (IS). In practice research case studies and other forms of intervention in local practices are central. Such studies require cooperation with practitioners. A researcher’s motives for conducting case studies are primarily to collect and analyze data for research purposes. A practice researcher also aims to develop scientific contributions of practical value. This article elaborates on the practitioners’ motives for participating in practice research using the case of a knowledge initiative (KI) concerning IS maintenance and evolution as an empirical example. KI has been arranged as a professional community in which practitioners (as KI members) and researchers have worked together to develop knowledge. By analyzing patterns of the KI members’ statements and engagements, we identify some tentative motives for practitioners to participate in practice research. The results show that their main motives are to influence research, increase their competence, being a part of a social community, and solve specific problems. With this in mind we are able to arrange for practice research cooperation that meets both researchers’ and practitioners’ motives. The article is concluded with key issues for organizing successful practice research collaboration