The statewide implementation of instructional support teams (ISTs) in Pennsylvania is analyzed in terms of the challenge of bringing team-based problem-solving models to scale. The history of the phase-in of ISTs in more than 1,700 elementary schools is presented, and the salient research conducted on ISTs is reviewed. The results indicate that ISTs are effective in reducing referrals to special education and improving measures of academic learning time. Recommendations for widespread adoption of problem-solving teams are contextualized in a three-tier model of service delivery. Within this model, the use of problem-solving teams of teachers analyzing group data for the purpose of restructuring whole-group instruction is proposed as a method of assisting schools in meeting the requirements of the No Child Left Behind Act.