Colorectal cancer is second only to lung cancer as a cause of cancer death in the United States. Studies have shown that fecal occult blood (FOB) tests are effective in detecting colorectal cancer in its early stages. To increase the participation in the FOB test among the working population, a randomized controlled trial was conducted. A total 278 federal employees 40 years or older in Washington State were randomly divided into a intervention group which received a Colorectal Cancer Risk Appraisal and a control group which received a simple information letter. After three months a follow-up questionnaire was sent to all participants to measure the effectiveness of the intervention. As a result of the study, the intervention group had a 4.3% higher compliance rate with the FOB test during the three month follow-up period (p = .10). The largest effect of the intervention was on the employees' intention to get a FOB test within the next year (62.6% in the intervention group vs. 36.2% in the control group, OR = 3.18, p < .001).