The purpose of this study was to compare the effect of brief walks completed in outdoor and laboratory environments on affective responses, enjoyment, and intention to walk for exercise. Thirty-five active young women (M age = 22.14 years, SD = 1.73) walked for 10 min at a self-selected intensity in outdoor and laboratory environments. Affective responses were assessed before, during, and following each brief walk. Enjoyment and intention also were assessed following each walk. Results revealed that although both walks resulted in improvements in affective responses, participants reported greater pleasant affective states, enjoyment, and intention for future participation with outdoor walking. Results of correlation analyses also revealed that affective responses were only consistently related to enjoyment in the outdoor environment. These findings suggest that the environment influences the affective responses to brief walks and show that affective states experienced during walking are related to theoretical determinants of physical activity. (Contains 3 tables.)