Epidemiological data show that mental illness in primary healthcare settings is a major public health burden.*The cost-offset model suggests that proper diagnosis and treatment of mental illness may result in better patient outcomes, and that the costs incurred are offset by savings in other medical expenses. Health economist Dr Andreas Pleil of the Upjohn Company reviewed the economic impact of mental illness and explained the use of the cost-offset model to delegates attendingOutcomes '95[Washington, DC, US; March 1995].