A workplace health education program aimed at reducing unnecessary outpatient visits was offered through 22 California employers. A total of 5,200 employees attended a presentation, received self-help books, and completed self-administered questionnaires. All visits for their households were monitored for up to 15 months. The study utilized a quasi-experimental staggered intervention design involving eight different cohorts, before/after comparisons, with statistical adjustment for seasonality and other intervening variables. Visit rates for households insured only by Blue Cross of California were reduced by 17% (P = 0.001), or 2.0 visits per household per year. For all participants, the reduction was 7.2% (P = 0.06), or 0.8 visits. Reductions were seen for all age and educational strata. The program was most effective among households with first dollar fee-for-service insurance coverage. Households with insurance requiring co-payments had less reduction. No reduction was seen among health maintenance organization (HMO) members. The study concludes that a minimal cost, self-care workplace intervention can reduce outpatient visits by important magnitudes.