Interventions training parents of at-risk children have received considerable empirical support but their effectiveness is undermined by low attendance rates. This research sought to clarify why parents, even with the best of intentions, fail to follow through to full participation in workshop programs; and to provide insight into ways to improve parental engagement. We examined participation in Parents as Partners, a school-based, early childhood intervention. Demographic and ongoing educational, social, emotional and behavioural data for 136 parent–child dyads were gathered from parents, teachers and children. Mitigation of a wide range of factors previously identified as barriers to attendance was also attempted. A post-intervention survey was conducted to examine parents’ insights into their attendance patterns. Overall, 91 parents attended and 44 failed to attend any workshops. Higher parent education and SEI, and better child language skills were good predictors of attendance (87%), but poor predictors of nonattendance (42%). Additionally, parent-child dyad profiles suggested that children of nonattending parents were more likely to benefit from workshop content than attenders’ children. Survey data suggested that attenders organised their schedules to facilitate follow-through but nonattenders were unable to do so. Family characteristics and practical reasons were central, interacting factors affecting attendance. Parental self-organisation appeared to moderate follow-through and to stem from lifestyle constraints related to lower SEI and parent education. This produced high nonattendance rates in parents of children who most needed support. It is urgent to discover to what extent innovative delivery platforms currently being explored (e.g., internet/social media) can improve parental engagement.