This study examines the impact of two considerations of a questionnaire's appearance on response rates. Factors of questionnaire color and a user-friendly format are evaluated as part of a follow-up mail survey to a corporate-sponsored incentive program. In response to a mailing of more than 3,500 questionnaires, it was found that appearance variations of the questionnaire resulted in significantly higher response rates. The content and questions asked in the survey did not vary. In a review of past literature dealing with questionnaire response rates, it was determined that past studies addressed structural, functional, and incentive characteristics that impact on changing response rates. Whereas the literature has not previously addressed the concept of a user-friendly format, there is some research exploring the response rates to color questionnaires versus black and white questionnaires. Previous studies have not found an increase in response rate as a result of the use of color in questionnaire design. This study, however, found color and/or a user-friendly format to be of significant value for increasing mail survey response rates.