This study focused on the development of the Problem-Solving Team Effectiveness Scale, a measure used by practitioners to assess the professional learning of a problem-solving team (PST) engaging in the technical aspects of intervention selection, implementation, and evaluation. Several best practices by PSTs were initially identified through a review of the literature: knowledge of interventions and intervention effectiveness, data-based decision-making, intervention integrity, social validity, follow-up consultation with a problem identifier, and support for the PST. Together, these practices constitute an intervention technology for PSTs. After content validation, completion of the 25-item measure by PST members in four states from the Midwest United States yielded a five-factor solution via exploratory analysis, and subsequent parallel analysis reduced the solution to three factors: social validity, knowledge of interventions and intervention integrity, and follow up with problem identifiers. These subscales consistently differentiated PSTs with high meeting integrity, defined as use of a timekeeper and agenda, from those with lower meeting integrity. Additionally, a pattern of statistically significant correlations emerged between the subscales and typical PST activities, thereby contributing to the instrument's convergent and discriminant validity. Discussion focuses on refinement of the scale as a professional development tool to enhance intervention technology with practising PSTs.