This guidance brief is the third installment in a four-part series being developed under the SCALA programme to support private sector engagement in climate action for agrifood systems. It provides step-by-step guidance on designing transformational adaptation projects that actively engage private sector actors and accelerate adaptation outcomes. Aimed at country planners, the brief offers practical advice on conceptualizing and structuring projects that align with national adaptation priorities while attracting private sector participation and investment. Ultimately, it seeks to help countries move beyond isolated, small-scale interventions towards transformative adaptation at scale, with private sector engagement as a key driver.