To assess the feasibility of a pediatric primary care based intervention to promote healthful behaviors among 0-6 month old infants and their mothers. We enrolled two intervention practices (60 mother-infant pairs) and one usual care control practice (24 pairs) in a non-randomized controlled trial. We completed visits and interviews with 80 (95%) pairs at birth and 6 months. The intervention included (1) brief focused negotiation by pediatricians, (2) motivational counseling by a health educator, and (3) group parenting workshops. We evaluated the intervention effects on infant feeding, sleep duration, TV viewing, and mothers' responsiveness to satiety cues. Maternal behavioral targets included postpartum diet, physical activity, TV and sleep. At 6 months, fewer intervention than control infants had been introduced to solid foods (57% vs. 82%; P=0.04), and intervention infants viewed less TV (mean 1.2 vs. 1.5 h/d; P=0.07). Compared to control infants, intervention infants had larger increases in their nocturnal sleep duration from baseline to follow up (mean increase 1.9 vs. 1.3 h/d; P=0.05); larger reductions in settling time (mean reduction -0.70 vs. -0.10 h/d; P=0.02); and larger reductions in hours/day of nighttime wakefulness (mean reduction -2.9 vs. -1.5 h/d; P=0.08). There were no differences in breastfeeding, response to satiety cues, or maternal health behaviors. A program of brief focused negotiation by pediatricians, individual coaching by health educators using motivational interviewing, and group parenting workshops tended to improve infant feeding, sleep and media exposure, but had less impact on mothers' own health-related behaviors.