A changing landscape in collection development

Ryerson University Library has been exploring different just-in-time acquisition models that provide us with cost-effective ways to purchase monograph titles with guaranteed usage. Based on our experience with Ebrary on the PDA (Patron Driven Acquisitions) Pilot, and with YBP on the DDA (Demand Driven Acquisitions) project, this discussion will focus on the theory behind our approach, the technicalities of implementation, and implications for future collection development strategies.