There are many challenges in developing evidence-based physical activity guidelines for preschoolers that can ensure health benefits for children. Guidelines for the preschool years have recently been developed in several countries, but there are notable inconsistencies in the amount of physical activity regarded as sufficient for this age group. Given the currently high prevalence of childhood obesity, there is an urgent need for evidence-based studies to inform the development of community-targeted programs to ensure healthy levels of physical activity in young children. Our article outlines the global recommendations for physical activity for children ≤ 5 years of age. We identify gaps in the literature and suggest recommendations for future research and public health policy.