To examine yoga's effects on inner-city children's well-being. This pilot study compared fourth- and fifth-grade students at 2 after-school programs in Bronx, New York. One program offered yoga 1 hour per week for 12 weeks (yoga) and the other program (non-yoga) did not. Preintervention and postintervention emotional well-being was assessed by Harter's Global Self-Worth and Physical Appearance subscales, which were the study's primary outcome measures. Secondary outcomes included other measures of emotional well-being assessed by 2 new scales: Perceptions of Physical Health and Yoga Teachings (including Negative Behaviors, Positive Behaviors, and Focusing/relaxation subscales). Preintervention and postintervention, physical well-being was assessed by measures of flexibility and balance. Subjective ratings of yoga's effects on well-being were evaluated by an additional questionnaire completed by the yoga group only. Data were collected from 78% (n=39) and 86.5% (n=32) of potential yoga and non-yoga study enrollees. No differences in baseline demographics were found. Controlling for preintervention well-being differences using analysis of covariance, we found that children in the yoga group had better postintervention Negative Behaviors scores and balance than the non-yoga group (P<.05). The majority of children participating in yoga reported enhanced well-being, as reflected by perceived improvements in behaviors directly targeted by yoga (eg, strength, flexibility, balance). Although no significant differences were found in the study's primary outcomes (global self-worth and perceptions of physical well-being), children participating in yoga reported using fewer negative behaviors in response to stress and had better balance than a comparison group. Improvements in well-being, specifically in behaviors directly targeted by yoga, were reported. These results suggest a possible role of yoga as a preventive intervention as well as a means of improving children's perceived well-being.