Abstract:The transportation sector is one of the largest contributors to greenhouse gas (GHG) emissions, driving climate change and corresponding consequences that affect the livability of communities across the world. To address climate change, transportation-related policies and programming are a requirement. In this chapter, we first address whether and how land use and transportation research might inform policies aimed at reducing GHG emissions. This chapter then explores a relevant case study-15 years’ worth of implementing mandates to reduce GHGs in California, the fifth largest economy in the world, through policies to improve land use and transportation coordination. These California policies provide an important model for considering how and whether GHGs can be reduced through promoting more efficient development and transportation patterns, thereby reducing the need to drive.