There is currently much interest in exploring environmental approaches to combat weight gain and obesity. This study presents process evaluation results from a workplace-based study that tested two levels of environmentally focused weight management interventions in a manufacturing setting. The moderate treatment featured a set of relatively simple, low-cost environmental modifications designed to facilitate healthy eating and physical activity; the intense treatment added elements intended to actively involve and engage management in program efforts. Fidelity varied across the 11 interventions comprising the two treatment conditions but did not vary systematically by treatment condition (moderate vs. intense). Environmental assessments showed improvements in workplace supports for weight management and significant differences by treatment level. Positive shifts in health climate perceptions also occurred, but sites receiving the intense treatment were not perceived as more supportive by employees. Challenges and limitations associated with environmental interventions are discussed with specific reference to activating management support. (Contains 7 tables.)