This series, Topics in TA, is being produced by NECTAC staff to share with our colleagues and others who are interested in the research on and practice of technical assistance. We will address various topics drawing from relevant literature and our experience in providing technical assistance. The impetus for this series is in large part to honor our late director, Pascal 'Pat' Trohanis, who guided and inspired us for 35 years. Pat was a consummate collaborator and greatly enjoyed sharing with and learning from our TA colleagues in and outside of the OSEP-funded TA & Dissemination network. This first paper is one he originally prepared to share with that network and concerns systemic changes in service systems. We welcome your comments on this paper and the series.