Environmental tobacco smoke (ETS) is a significant public health burden. This review summarizes empirical evidence for reducing residential ETS exposure in youth in 19 studies published between 1987 and 2002. Most studies have investigated minimal contact, physician office-based interventions, although some have been conducted in homes and have been more intensive. Interventions are compared based on study design, type of intervention, sample characteristics (asthmatic or healthy), goals, and outcomes, including effect sizes. The average effect size (Cohen's d ) was .34, with a range from -.14 to 1.04. The evidence suggests that interventions can be effective in reducing children's exposure. More rigorous study designs, interventions of greater intensity and duration, and those based on sound behavior change theory have yielded the most promising results. Challenges and limitations in this area of study are examined. A model for ETS interventions is proposed, and directions for future research are set forth.