This study describes the process evaluation of the Supporting Physical Activity in the Childcare Environment (SPACE) intervention, consisting of educator physical activity training, provision of portable play equipment, and a modified outdoor schedule (i.e., 4 × 30-minute periods). Educators (N = 49) from 11 childcare centers in London, Ontario, Canada, delivered the 8-week intervention to 200 preschoolers (M[subscript age] = 3.38 years). Workshop attendance was documented while adherence to the outdoor schedule and number and timing of outdoor sessions offered (i.e., dose) were recorded in a daily log. Questionnaire-based program evaluation (n = 41) and in-person group interviews (n = 7) were completed postintervention to assess educator perspectives on the "barriers and facilitators" to implementation (i.e., "context"), the "feasibility" and "perceived effectiveness" of the intervention, educator and preschooler "enjoyment, communication" among researchers and childcare personnel, and the "future implementation" of the intervention. Descriptive statistics were calculated, and responses to open-ended questions were inductively coded. Educator workshop attendance was 96%, and 88% of classrooms adhered to the four daily outdoor periods. Educators delivered 90% of the scheduled outdoor sessions, and 87% of these met the 30-minute criteria. Educators expressed that the increase in number of transitions made the outdoor playtimes challenging to implement, yet rated the feasibility of the training and equipment as high. Educators perceived the intervention to be both enjoyable and effective at increasing preschoolers' physical activity. They indicated effective communication and revealed that they intended to continue to use their physical activity knowledge and to offer the play equipment once the intervention had concluded. These findings demonstrate that the SPACE intervention is viable in center-based childcare.