BACKGROUND We conducted a pilot test of American Cancer Society Workplace Solutions, an intervention that takes a marketing approach to increasing employers' adoption of evidence-based practices to prevent and control chronic diseases among their employees. CONTEXT We delivered the intervention and assessed the changes in practices of 8 large employers in the Pacific Northwest. METHODS Workplace Solutions recommends 15 employer practices in 5 categories: 1) health insurance benefits, 2) policies, 3) workplace programs, 4) health-promoting communication, and 5) tracking of employee health behaviors to measure progress. The intervention includes 4 meetings with employers over 2 months and begins with a questionnaire-based assessment of employer practices. Tailored recommendations follow, along with practice-specific implementation assistance on requested topics. We tested the intervention in a before-after study without a comparison group. CONSEQUENCES The employers ranged in size from 7500 to 115,522 employees and included private companies and public employers. Seven of the eight employers implemented more of the recommended practices at follow-up (an average of 13 months after the intervention) than at baseline. Overall, implementation of the practices increased from 38% at baseline to 61% at follow-up (P = .02). INTERPRETATION Workplace Solutions is a promising new approach to bringing evidence-based best practices for preventing chronic disease to large numbers of adults.