- Summary: In light of Head Start's recent move toward longer program implementations, the current study examined whether the duration of Head Start enrollment impacts outcomes for parents: parental involvement in school, perceived helpfulness of social support, and use of formal social services. - Findings: Linear mixed model analyses examined whether parental outcomes differed depending on the number of years enrolled in Head Start. Parents whose child enrolled more years in Head Start were more likely to participate in their children's schools and received more helpful social support than those whose child enrolled in fewer years of Head Start. No difference was found for formal social service use depending on longer duration of Head Start enrollment. Minority status, household risk factors, and non-English speaking were negatively associated with parental outcomes. - Applications: Early intervention programs, such as Head Start, should recruit eligible low-income families earlier for longer participation on family-focused programs. (author abstract)