In 2004, California's Paid Family Leave Insurance Program (PFLI) became the first state program to provide paid leave to care for an ill family member. To assess awareness and use of the program by employed parents of children with special health care needs, a population likely to need leave. Telephone interviews with successive cohorts of employed parents before (November 21, 2003-January 31, 2004; n = 754) and after (November 18, 2005-January 31, 2006; n = 766) PFLI began, randomly sampled from 2 children's hospitals, one in California (with PFLI) and the other in Illinois (without PFLI). Response rates were 82% before and 81% after (California), and 80% before and 74% after (Illinois). Taking leave, length of leave, unmet need for leave, and awareness and use of PFLI. Similar percentages of parents at the California site reported taking at least 1 day of leave to care for their ill child before (295 81%) and after (327 79%) PFLI, taking at least 4 weeks before (64 21%) and after (74 19%) PFLI, and at least once in the past year not missing work despite believing their child's illness necessitated it before (152 41%) and after (156 41%) PFLI. Relative to Illinois, parents at the California site reported no change from before to after PFLI in taking at least 1 day of leave (difference of differences, -3%; 95% confidence interval CI, -13% to 7%); taking at least 4 weeks of leave (1%; 95% CI, -9% to 10%); or not missing work, despite believing their child's illness necessitated it (-1%; 95% CI, -13% to 10%). Only 77 parents (18%) had heard of PFLI approximately 18 months after the program began, and only 20 (5%) had used it. Even among parents without other access to paid leave, awareness and use of PFLI were minimal. Parents of children with special health care needs receiving care at a California hospital were generally unaware of PFLI and rarely used it. Among parents of children with special health care needs, taking leave in California did not increase after PFLI implementation compared with Illinois.