States play a critical role in authorizing financing mechanisms and providing resources to support low carbon technologies and activities. This often involves partnerships or leveraging of financing programs at the federal and local levels, as well as collaboration with private lenders, industry, commercial entities, and homeowners to stretch the limited available dollars and cents. Traditional financing programs include tax breaks, rebates, and other incentives to modify procurement practices and behaviors in support of energy efficiency, renewable and energy, and other clean and green energy activities. In addition, a variety of innovations in financing have supported new methods to open financial resources in support of alternative energy consumption or conservation and efficiency programs. Often these investments have long-term net benefits to firms, government, and society, but there is an ongoing need to encourage spending in these areas. Before discussing the state role and the financing policy tools, this chapter will start with the justification for governmental intervention into this aspect of the economy.