This document discusses strategies for maximizing the use of slave databases in MySQL replication. It begins by outlining some common problems with scaling through multiple slaves, such as high write rates limiting reads per slave and inefficient slave resource utilization. It then provides recommendations for reducing write rates through query optimization and selective data replication. The document also discusses ways to better utilize slave resources like specialized storage engines and indexes on different slaves. Finally, it covers approaches for applications to integrate reads from slaves while handling stale data, such as query-based, session-based, and data versioning techniques.