This study investigated the ways in which family members of students in a Hawaiian language immersion program were involved in their children's education and identified the effects of and barriers to involvement. A sociocultural theoretical approach and Epstein's framework of different types of involvement were applied. Participants included 35 families whose children were enrolled in Papahana Kaiapuni, a K-12 public school program in Hawai'i. The program uses the Hawaiian language as the medium of instruction. Semi-structured interviews were conducted with participants about their program experiences. Kaiapuni family involvement practices were consistent with Epstein's typology. Consistent with previous research on family involvement in other contexts, Type 2 (school-home communications) and Type 3 (voluntary involvement) were prevalent. However, different from previous reports, participants were more involved in school decision making (Type 5). Families felt that their involvement promoted (a) the development of children's values, (b) family and community bonding, (c) children's English language learning, and (d) family members' learning about Hawaiian language and culture. The most frequently mentioned barrier to involvement was a lack of proficiency in the Hawaiian language.