This chapter examines the role of grassroots innovations and other closely relative local initiatives in the efforts to implement housing retrofits and community development in Worcester, Massachusetts. The recent developments in Worcester with respect to housing, energy, and community have allowed us to shed light on how such multi-stakeholder engagement may work in reality and what the barriers and opportunities are. The case study describes two streams of initiatives, with their different framings and objectives, which came together in a deeply interactive way in the Worcester locality: one represents a business-led approach to energy conservation and renewable energy by way of developing a technology cluster. The Institute of Energy and Sustainability represents this approach. The second is a grassroots initiative; a platform of many stakeholders and academics aiming to create a systemic approach to energy conservation in housing while at the same time advancing community development goals. The Worcester Housing, Energy, and Community group (WoHEC) represents this approach.