<p>This study explores the foundational elements critical to team success, emphasizing the importance of team leadership and clear roles and purpose. Drawing on the theoretical framework by Zajac and colleagues (<CitationRef CitationID="CR16">2021</CitationRef>), the study identifies three levels of team effectiveness: Foundations; Attitudes, Behaviors, and Cognitions; and Ideal Team States. It highlights starting at the Foundations level and what is within the team’s direct control, showcasing that team leadership and role clarity are pivotal in setting the stage for team success. The research involved a performance improvement program with participants from multiple healthcare and higher education organizations (<i>N</i> = 78, <i>N</i> = 81 for team leadership and clear roles and purpose, respectively). Exploratory Factor Analyses supported the proposed three-factor structures for both Team Leadership and Clear Roles and Purpose, revealing high factor loadings (ranging from 0.448 to 0.960) and significant variance explained. The findings underscore the importance of the foundational elements within teams and offer practical insights for enhancing team cohesion and effectiveness, particularly in complex environments like healthcare.</p>