Heat islands are a phenomena where urban and suburban temperatures are 2-10 degrees (F) higher than nearby rural areas, resulting in increased peak energy demand and air pollution levels. Strategies to reduce heat islands can reduce the emissions that contribute to global warming. The HIR initiative works with target groups to identify opportunities to implement heat island reduction strategies such as cool roofs, cool pavements, and additional trees and vegetation. Heat island reduction strategies include: Installing cool or vegetated green roofs; Planting trees and vegetation; and Switching to cool paving materials. HIRI supports research to better understand the impacts that heat island reduction strategies have on urban meteorology, air quality, energy demand, and human health. The program translates this research into outreach materials, tools, and guidance that provide communities with information to develop programs, policies, codes, and ordinances to implement heat island reduction strategies.