This comparative study explored the influence of different pre-school models on school readiness among pre-school children from different urban socio-economic status (SES) neighbourhoods. The study sampled 207 pre-school children attending different pre-school models in different SES neighbourhoods within the city of Nairobi in Kenya. In the study, school readiness was conceived as the ability of children to learn and handle primary school tasks. Assessment was done through teachers' rating of children's level of developmental and fitnctional skills using a School Readiness Assessment Instrument (SRAI), which was adopted and modified from the Early Development Instrument (EDI). The study compared school readiness outcomes amongst pre-schoolers aged five and six years. School readiness outcome was also correlated with the level of developmentally appropriate practice of the different pre-schools, assessed through observation and interviews. Major findings from this study were that, pre-school children who attended Private pre-school models outperformed their peers from public pre-schools in school readiness scores and children from low SES neighbourhoods had lower school readiness scores compared with children from middle and high SES neighbourhoods. The study recommends a paradigm shift from an academically oriented pre-school model to one that embrace a holistic approach in program and assessment of children's school readiness. It also recommends further studies on the influence of cultural variations on school readiness and primary school readiness to receive pre-schoolers.