This report presents the results of the Parental Involvement in Pre-School Telephone Interview study completed by Mathematica Policy Research for the First 5 Contra Costa Children and Families Commission. Parent involvement in children's preschool programs and learning experiences is proven to be positively associated with cognitive, academic, social-emotional, and behavioral development. This report provides insight into parent opinions of and involvement with child care programs participating in Preschool Makes a Difference (PMD) and offers First 5 Contra Costa new accounts of how PMD programs help to support the diverse needs of Contra Costa parents. The report is informed by 30 parent interviews conducted in December 2009 and January 2010. Interviewees were selected from a list of 100 parents who had children enrolled in programs participating in Contra Costa PMD and who had previously agreed to be contacted for a possible interview. The first section of the report summarizes the interview process and characteristics of parents who provided interviews. The second section offers an overview of parent responses organized around three core questions: (1) how did parents select afterschool programs, (2) how have programs helped parents become involved with learning at home, and (3) how did parents define quality. Following is a summary of the primary findings. Appended are: (1) Methodology; (2) Final Parent Involvement Interview Protocol; and (3) Coding Guide for First 5 Contra Costa Parent Involvement Report. (Contains 7 tables.)