In 2008, Macquarie University instituted the Participation and Community Engagement (PACE) initiative. This initiative embeds units in the curriculum that involve learning through participation (LTP) that is mutually beneficial to the student, the University and the organisation or community in which student participation activities take place. Ethical practice is thus an integral part of this initiative. The issue of ethical practice in LTP "has not been comprehensively addressed in the literature to date" and warrants further examination. This paper discusses the development of the innovative PACE Ethical Practice Module to teach ethical practice in participation units. We evaluate the effectiveness of the Module using a mixed methodology and present preliminary findings on students' perceptions before and after their participation activity, and evaluations by academic convenors of participation units. We conclude by discussing the implications for future iterations of the Module and teaching ethics in PACE. [Papers included in this "Asia-Pacific Journal of Cooperative Education" ("APJCE") Special Issue stem from selected manuscripts from the Australian Collaborative Education Network Annual Conference 2012.]