This document discusses activities of WorkStream 4 of the African Cassava Agronomy Initiative project. It provides an overview of the general approach, which is to develop and facilitate use of site-specific agronomy recommendations at scale. It discusses project outcomes such as targeted increases in cassava root yield and additional supply to processing industries. It also outlines various dissemination activities including training events, promotion events, and demonstrations. Finally it discusses monitoring, evaluation and learning activities and timelines for decision support tool development and validation in 2019-2020.