Objective: To assess the effectiveness of a home-based early intervention on infant feeding practices and "tummy time" for infants in the first year of life. Design: Randomized controlled trial with follow-up measures scheduled at 6 and 12 months. Setting: Socially and economically disadvantaged areas of Sydney, Australia. Participants: We recruited 667 first-time mothers and their infants in 2007 and 2008. Interventions: The intervention consisted of 5 or 6 home visits from a specially trained research nurse delivering a staged home-based intervention in the antenatal period and at 1, 3, 5, 9, and 12 months. Main Outcome Measure: Changes in infant feeding practices and "tummy time." Results: The intervention group had a significantly higher median duration of breastfeeding at 12 months than the control group (17 weeks [95% confidence interval, 13.9-20.4 weeks] vs 13 weeks [95% confidence interval, 10.1-15.0 weeks]; P=.03). Compared with the control group, the hazard ratio for stopping breastfeeding in the intervention group was 0.82 (95% confidence interval, 0.68-0.99). The intervention also resulted in a significantly later introduction of solid foods (P<.001 for trend), reducing the proportion of mothers who introduced solids before 6 months by 12% (95% confidence interval, 4%-20%) from 74% to 62%. The intervention also decreased the age at which infants started tummy time (P=.03 for trend) and increased the daily practice of tummy time by 7% from 76% to 83% (P=.05). Conclusion: The home-based early intervention delivered by trained community nurses significantly improved some infant feeding practices and resulted in earlier daily practice of tummy time. Trial Registration: anzctr.org.au Identifier: ACTRNO12607000168459.