The Transportation Land Use, Planning, and Air Quality Conference 2009, held on July 28 and 29 in Centennial, Colorado, provided a forum to examine the challenges of balancing increases in travel demand with growing air-quality concerns by emphasizing the latest research coordinating the advancements and environmental impacts of transportation. The main focus of the conference was the "moving cooler" study, implemented by various federal agencies, state and local governments, and interest groups with the goal of evaluating a broad range of climate change strategies. This proceedings includes selected, peer-reviewed papers that were presented at the conference, covering topics such as: Ø environmental impacts of freight Ø effect of fuel prices Ø integrating land use into transit systems planning Ø climate change, emissions, and air-quality models Ø land-use models Ø advancements in computing technology and modeling The papers in this proceedings will be of great value to engineers working in the fields of climate change, transportation, and land use.