The American Medical Informatics Association (AMIA) Visual Analytics Working Group (VIS WG) established a Task Force on Evaluation (TFoE) in early 2016 to investigate the state-of-the-art in visual analytics evaluation and to provide a report documenting recommendations for visual analytics evaluation within the context of the medical informatics domain. This progress report documents the history of this task force, including its mandate and membership. This report also provides a brief summary of progress made so far, outlines future plans, and describes how additional members of the community can participate.