This project brings together applied naturalistic research data to assess the impact of employee assistance program (EAP) services on employee work, stress, and health. Clinical and follow-up self-report survey data from one EAP company (Optum®) is analyzed representing four large national samples (N > 1000 cases randomly selected each year for 1999, 2000, 2001 and 2002). Results show that the majority of EAP clients report improvements in their work productivity and avoided absenteeism, stress, overall health and well-being and daily functioning after use of the service. The findings are found consistently in each year’s data and thus provide replication of results. Financial estimates of workplace outcomes are provided.