This study uses GIS to examine the constrained daily geographies of working poor women in order to assist transportation planners in understanding underserved populations and identifying gaps in transit service. Through interviews and travel diaries, I have uncovered constraints on daily travel in a sprawling, medium-size American city (Knoxville, Tennessee). This study undermines the too-optimistic assumptions generated by analyses of aggregate-level data, in that the transition from welfare to work will not be as smooth, nor as uniform, as aggregate data indicate. Based on this research, I recommend increased investment in car ownership and related assistance. Access to cars will not only increase working poor women’s daily mobilities, but also their job opportunities, overall earnings, and – ultimately – their successful and permanent transitions from welfare to sufficient and satisfying work.