One hundred and sixty-four children from a rural county in the state of Maryland, USA, were followed longitudinally from birth until kindergarten entry, tracking their participation in a home visiting program designed to enhance parent child interaction and school readiness. Results suggest that duration of home visiting had a positive, direct effect on home safety and parental knowledge of infant development. Home safety had a positive direct effect on overall school readiness regarding personal and social competence, language and literacy, mathematics and physical health and development, although the effect size for mathematics was smallest. Home visiting duration using Parents as Teachers (PAT) had an indirect effect on school readiness through home safety, suggesting that as families receive more direction on ways to promote positive learning outcomes, home safety scores rise and school readiness scores increase. Implications for program and policy development including universal services are discussed. (Contains 2 tables.)