Abstract Introduction The Sleep More, Stress Less Program (SMSL) is a University of Alabama (UA) employee wellness program designed to help participants implement health behavior changes to improve sleep quality and stress management. Workplace wellness programs offer a win-win for the employee and employer through improved health and reduced absenteeism. However, many programs fail to show effectiveness on health and workplace metrics, even with an increase in targeted health behaviors. This may be due—at least in part—to employee self-selection and data collection limitations. The SMSL program addresses these challenges by recruiting employees experiencing sleep and stress issues and using a rigorous assessment approach that records data on behavior changes, process goals, intermediate mechanisms, and health outcomes. We present findings from the SMSL program evaluation conducted Fall 2020. Methods The SMSL program is delivered online with both synchronous and asynchronous content (videos and exercises). The content combines evidence-based interventions for sleep and stress with the science of behavioral motivation. All adult (19–99 years) UA employees were eligible and recruitment occurred through the WellBama website and employee emails. Employees are encouraged to select programs that match their health issues. Participants complete an online pre-program assessment and track their sleep and stress for one week. Next, participants complete the SMSL educational program over the next three weeks. In the fifth week, participants track their sleep and stress and complete the online post-program assessment. Results 60 of the initial 85 participants completed all assessments (70.5%). Participants were primarily Female (79%) and Caucasian (77%) or Black (15%), and aged 24–68 (m=44) years. Moderate improvements were reported in total sleep time, sleep maintenance, and time to return to sleep after awakening. Similar improvements were observed in stress scores. Qualitative evaluation of participant behavior goals revealed a focus on sleep scheduling, stimulus reduction, and relaxation. Conclusion Employee wellness program evaluation is often affected by selection and measurement bias. The SMSL program targeted individuals experiencing stress and/or sleep problems and measured multiple outcomes to identify benefits over the 5-week program. Other wellness programs would benefit from this approach in order to capture true program outcomes. Support (if any) N/A