As more and more chapters develop and implement their GLAM outreach programs, it is time to talk about evaluation again. An earlier workshop on this topic was held at Wikimania 2013 in order to reach a shared vision of what may be achieved by different types of GLAM outreach activities. The results have been documented on the Outreach Wiki. In parallel, the WMF Programme Evaluation team has produced several evaluation reports about programs including one on GLAM content release partnerships, and the GLAM-wiki Toolset Project coordinated by the Europeana Foundation and supported by Wikimedia Netherlands, Wikimedia France, Wikimedia UK, and Wikimedia CH has produced a Report on requirements for usage and reuse statistics for GLAM content. As we work as a community to further develop evaluation strategies and systematic measures we invite community members engaged in GLAM outreach activities to take part in this strategy workshop.