Background Adult-child relational interactions constitute an essential component of out-of-school-time programs, and training staff to effectively interact with children is key to improving program quality. Efficient staff training, that meets the limited time availability of out-of-school time staff, is particularly needed. Objective This pilot study introduces Simple Interactions (SI), an innovative, strengths-based, and interaction-based professional development approach. Rather than attempting to teach generic competencies or targeting weakness areas for improvement, SI is designed to help program staff build from their strengths. Methods In two cohorts over the course of 10 months, ten afterschool programs (N = 70 staff) participated in a pilot of SI. Program staff watched short video clips of themselves working with children and used the intuitive, 1-page SI Tool to guide discussion of adult-child interactions; specifically, connection (affective intune-ness), reciprocity (balanced roles of engagement), participation (involving all children), and progression (incremental challenge). Results Results suggest that participants valued the professional development process, the strengths-based approach, and the use of self-video despite initial apprehension, and reported perceived improvements in their professional learning communities. Pre-post videos of Cohort 2 staff (n = 20), coded blind to time point (pre or post), indicate significant and substantive improvements in staff-child connection, reciprocity, and participation. Conclusion These results support the use of this simple, practical, and potentially effective model of supporting quality improvement for and by local staff. (author abstract)