Background: Infant attachment security is a protective factor for future mental health, and may be promoted by individual interventions. Given service demands, it is important to determine if a group-based intervention for parents could be used to enhance infant attachment security. Methods: In a randomized trial involving 76 mothers, an 8-session attachment group called "Right from the Start" (RFTS) was compared to home visiting (treatment as usual). Results: Intention-to-treat analyses indicated no significant differences between RFTS and home visiting, with both groups showing small improvements in infant attachment security and maternal sensitivity. RFTS cost significantly less and was more cost effective than home visiting, and was not significantly different in terms of participation ratings, client satisfaction, or follow-up service requests. There was differential compliance for the two interventions, with 89% and 58% attending 4 or more sessions of home visiting and RFTS, respectively. Secondary analyses considering non-attenders as a separate (nonrandomized) group indicated a significant advantage for those who attended RFTS on pre-test/post-test maternal sensitivity change scores (d = .52) and pre-test/6-month follow-up infant attachment security changes scores (d = .55). Conclusions: RFTS is as effective as home visiting in improving infant attachment security and maternal sensitivity. The effect sizes for RFTS were comparable to those of individual attachment interventions in this relatively inexpensive, community-based group intervention.