Comprising over 9 million units in this country, suburban multifamily housing is a widespread and overlooked example of density located within walking distance to commercial development in suburbia. This report focuses on resident demographics, attitudes, and perceptions as they relate to mode choice in 14 suburban multifamily sites in Eugene, Oregon. Through site analysis and resident surveys, our study shows that site design and connectivity is a significant predictor of resident mode choice. Residents of more-connected developments walk and bike to their local commercial area for more than 40% of their trips, nearly twice the rate of residents of less-connected developments. The greater use of active transportation versus auto transport in well-connected developments has potential environmental benefits of reductions in green house gas emissions, vehicle miles traveled, and gas consumption and the health benefits of increases in exercise and calorie burning, and the social benefits of increases in independence of elderly and youth populations. Quantifying the degree to which site design, and specifically connectivity, makes a difference in residents’ mode choice is a first step to increasing the amount of active transportation in these areas. The results of this research provide planners and designers a basis for reevaluating suburban multifamily site design and zoning codes.