Knowledge, attitudes, and practices regarding varicella vaccination and disease were assessed among health care providers participating in the Varicella Active Surveillance Project in Antelope Valley, California, in 2005. Compared with those of a similar survey conducted in 1999, results suggest a reduction in concerns about vaccine safety and efficacy. Routine assessment of adolescents for varicella susceptibility was reported by 87% of respondents, but only 42% reported routine assessment of adults. Several respondents were unaware that disease in a vaccinated person is infectious, and some did not know the vaccination recommendations pertaining to susceptible health care workers, suggesting a need for provider education on these issues.