This document summarizes a study of how patrons at three California State University campuses interacted with the Primo discovery system. The study analyzed analytics data from November 2017 to explore how patrons at campuses of varying sizes used Primo features like facets and scopes. The findings provide insights but also limitations, highlighting the need for more research through user testing and longer-term analytics. Key questions addressed how mobile use, required instruction, and collection size may impact discovery interactions.