In the face of persistent air quality problems, as well as emerging air quality concerns, such as greenhouse gases and state budgetary constraints, states are looking for new ways to maximize air quality while minimizing costs. RAP’s Integrated, Multi-Pollutant Planning for Energy and Air Quality (IMPEAQ) fosters long-range planning, multi-pollutant analysis, and cost optimization modeling to enable state air quality regulators to achieve efficient gains in air quality. In this white paper Columbia Law School assesses the general statutory and regulatory framework applicable to IMPEAQ as a voluntary program for states to adopt for their air quality planning. The paper first addresses threshold issues relevant to IMPEAQ: state authority under the Clean Air Act to voluntarily implement integrated planning using IMPEAQ and the permissibility of using a multi-pollutant approach to air quality planning. In addition, while this paper does not provide a detailed analysis of specific control measures, it examines two key issues concerning emerging control measures: how states can use energy efficiency and renewable energy (EERE) programs in their State Implementation Plans (SIPs) and to what extent states may allow novel measures to satisfy the Act’s source-specific control technology requirements.