Employing a quasi-experimental design, this pilot study on teacher practices with toddlers during social conflicts was conducted in the southeastern USA. Four child-care classrooms, teachers (n = 8) and children (n = 51) were assessed with the Classroom Assessment Scoring System - Toddler [CLASS-Toddler; La Paro, K., Hamre, B. K., & Pianta, R. C. (2011). Classroom Assessment Scoring System -Toddler (CLASS). Baltimore, MD: Brookes], an author-developed problem solving measure, a measure of child temperament and teacher interviews. Teachers in intervention classrooms were provided professional development in three areas: (a) teacher self-regulation and stress management, (b) child self-regulation of emotions and behaviours, and (c) social problem solving. For intervention classrooms, results showed growth in several CLASS dimensions including positive climate, teacher sensitivity, and classroom guidance, while the problem-solving measure revealed an unanticipated increase in problems. Additional research is needed on toddler social problem-solving skills and supportive teacher practices. Further refinement of the problem-solving measure and delineation of specific professional development intervention components that indicate positive classroom change is needed. (author abstract)