Understanding travel well-being is important for a better representation of travel behavior and for the design and evaluation of policies. This project aims at measuring travel well-being and modeling its causes and its relationship to travel behavior. This will be accomplished through two data collection efforts. The first one is a cross-sectional travel and activity well-being survey that was conducted with a sample of commuters starting in the summer of 2007. This survey was used to model commute well-being and to model the relationship between activity happiness and the propensity to participate in activities. The second data collection effort, starting in the summer of 2008, will measure travel well-being and mode choice decisions after an intervention requiring car commuters to switch temporarily to public transportation. The findings from these surveys and experiments will be used to develop a framework for transportation planning that includes travel well-being.