The promotion of physical activity (PA) in young children requires effective in terventions. This ar ticle reviews the evidence on PA interventions in child care by applying a socio-ecological a pproach. A computer-based literature search for intervention studies aimedatincreasingchildren ’ sPAlevelswasrunacrossfourdatabases:SPORTDiscus, ISI Web of Science, PsycINFO and ERIC. The participants had to be in childcare, aged 2-6-year-old, and their pre- and post- intervention PA levels measured. Selecti on was restricted to peer-reviewed publications and to studies conducted in childcare settings. Twenty-three studies met the inclusion criteria and their methodological quality was assessed. Seven studies ex hibited high methodological quality; twelve were rated as moderate and four low. The effectiveness of the interventions was det erminedaccordingtothepost -intervention behavioral changes reported in children ’ s PA. Fourteen studies found increases in PA levels or reductions in sedentary time, although the changes were modest. The data remain too limited to allow firm conclusions to be drawn on the effectiveness of the components mediating PA interventions, although PA-specific in-service teacher training seemsapotentialstrategy.Thefindingsofthisreviewindicatethatchildren ’ sPAremainedlowanddidnot approachthe180min/daycriteria.Itmaybethatmoreint ensive multilevel and multicomponent interventions based on a comprehensive model are needed.