This study examined how characteristics of parents, providers, and children contribute to the quality of parent-provider relationships in infant and toddler classrooms. Parents (n=192) and providers (n=95) from 14 child care centers in a large metropolitan area participated by completing questionnaires about the nature of their relationships and communication, as well as other aspects of the child care experience. Although the study did not examine causal relations between variables, characteristics of parent-provider relationships were correlated with parents' anxiety about placing their children in care, with providers' knowledge of child development, and with whether parents and providers had worked together in the past. Parents' views of their relationships with providers were more positive when they had worked with them before and when they were less anxious about placing their children in care. Providers who had worked with parents before had less favorable views of their relationships when parents were more anxious about placing their children in care; however, this was not the case when providers and parents were in more recent relationships. Providers who had never worked with parents before viewed relationships more positively when they had more knowledge of child development. The opposite was true for providers who had worked with parents before. Providers with more knowledge of child development reported communicating more frequently with parents. Providers reported communicating more frequently with parents of children with easier temperaments. (author abstract)