Although intensive early childhood interventions and high quality preschool programs have been shown to foster children's school readiness, little is known about the school readiness gains made by ethnically and linguistically diverse children in poverty receiving subsidies to attend center-based childcare or those in public school pre-kindergarten programs. Within the context of a large-scale, university-community applied research and evaluation project, The Miami School Readiness Project, children receiving subsidies to attend center-based childcare (n = 1478), children attending free Title 1 public school pre-k programs (n = 1611), and children attending fee-supported public school pre-k programs (n = 749) were individually assessed at the beginning and end of their pre-kindergarten year in the areas of cognitive, language, and fine motor development. Parents and teachers reported on children's socio-emotional strengths and behavior concerns. Findings revealed that although children from all types of programs made considerable school readiness gains in most areas in terms of their national relative standing, children attending public school pre-k programs typically made somewhat greater gains in the areas of cognitive and language development. Results suggest that center-based childcare programs in the community may be beneficial for fostering school readiness within ethnically diverse children in poverty, and that public school pre-kindergarten programs may show even greater gains in some areas. Policy implications are discussed. (Contains 4 tables and 1 figure.)