Cross‐sector partnerships (CSPs) are important for tackling development challenges across public, private, and non‐profit sectors. Despite their growing prevalence as partnership models of choice for grand challenge efforts, there is little evidence‐based understanding about the dominant features of these engagements. This makes it difficult to develop CSP engagement models that are useful across development problems and settings. We posit that CSPs are intrinsically cross‐disciplinary endeavors and require collaboration models that enable interdisciplinary problem orientation and solution casting. To facilitate sense‐making in partnership efforts, a CSP engagement model must therefore integrate perspectives on partnership from major disciplines and practitioner experiences. Using automated content analysis of peer‐reviewed publications and manual content analysis of practitioner interviews, we explored the robustness and relevance of partnership capacity theory (PCT), an interdisciplinary CSP engagement model, as an evidence‐based approach to CSP with best‐practice grounding. We found PCT comprehensively characterizes collaborative CSP dynamics and offers a foundational view of CSP best practices.