This document summarizes Holyoke, Massachusetts' efforts towards sustainability across several areas: power generation and efficiency, policies and ordinances, projects, and industry recruitment. Some key points are that Holyoke generates 94% of its retail power from carbon-neutral sources, has reduced municipal power usage by 21% since 2009, adopted green community policies and stormwater management ordinances, redeveloped and adapted historic buildings, renovated neighborhoods and parks, expanded transit options, and recruited green businesses like the Massachusetts Green High Performance Computing Center.