Walking is the most prevalent and preferred method of physical activity for both work and leisure purposes, thus making it a prime target for physical activity promotion interventions. We identified 14 randomized controlled trials, which tested interventions specifically targeting and assessing walking behavior. Results show that among self-selected samples, intensive interventions can increase walking behavior relative to controls. Brief telephone prompts appear to be as effective as more substantial telephone counseling. Although more research is needed, individual studies support prescriptions to walk 5-7 versus 3-5 d.wk and at a moderate (vs vigorous) intensity pace, with no differences in total walking minutes when single or multiple daily walking bouts are prescribed. Mediated interventions delivering physical activity promotion materials through non-face-to-face channels may be ideal for delivering walking promotion interventions and have shown efficacy in promoting overall physical activity, especially when theory-based and individually tailored. Mass media campaigns targeting broader audiences, including those who may not intend to increase their physical activity, have been successful at increasing knowledge and awareness about physical activity but are often too diffuse to successfully impact individual behavior change. Incorporating individually tailored programs into broader mass media campaigns may be an important next step, and the Internet could be a useful vehicle.