The articles included in this special issue of Quest emerged from a research workshop entitled "Thinking About Our Thinking in Adapted Physical Activity," held at the University of Alberta in Edmonton, Canada, from June 18-19, 2013. The aim of the workshop was to examine different worldviews that contribute to the adapted physical activity research literature, to identify key disciplinary assumptions, and to outline their consequences for multidisciplinary and interdisciplinary research in the field. A lack of understanding of the basic assumptions held by researchers often impedes communication between the disciplines. Hence, a sub-theme of this special issue is communication across disciplines. These conversations are, of course, essential to interdisciplinary inquiry.