Background: Evidence related to the effects of tobacco exposure in pregnancy and on infant and child health have focused on women's smoking cessation. Less often addressed is men's smokirig, which when continued in fatherhood, reduces the chances of female partners' cessation and can negatively impact children's health as well as men's health. Dads in Gear (DIG) is an innovative program designed specifically for new fathers who want to reduce and quit smoking that includes three components: smoking cessation, fathering, and physical activity. The over-arching purpose of this study is to evaluate the feasibility of the DIG program and provide estimates of program efficacy. The purpose of this article is to describe the rationale and protocol for evaluating the DIG program's feasibility, acceptability and potential effectiveness. Methods: Using a prospective, non-comparative design, the DIG program will be implemented and evaluated in six communities. The program will be offered by trained facilitators to fathers who currently smoke and want to quit. The RE-AIM framework will guide the evaluation. Open-ended questions in participant surveys, and semi structured interviews and weekly telephone de-briefs with facilitators will provide data for a process evaluation. Estimates of effectiveness include smoking behavior, fathering and physical activity measures at baseline, end of program, and 3-month follow up. Conclusion: The DIG program could support positive changes with respect to smoking cessation, physical activity and overall health for men. These effects could also promote family health. The program might also provide an effective model for engaging men in other health behavior change. (C) 2017 The Authors. Published by Elsevier Inc.