We investigate the role of the built environment in mode choice decisions for home-based work tours in the New York Metropolitan Region. The analysis is conducted using a multinomial logit model. There are two main results of this study. First, the built environment influences people’s mode choice decisions, even after controlling cost variables. Population and employment densities have explanatory power, so do the variables measuring the access distance between the nearest mass transportation facility and a stop in the tour. Second, tour characteristics do affect mode choices. Mode choice decisions shall be analyzed with tours as the analysis unit.