Early investigation led the Evaluative Study of Action Research (ESAR) team to conclude that the complexity of a global, large scale study (evaluation of more than 100 highly diverse action research [AR] projects) called for an overarching research evaluation framework that differed from traditional frameworks. This article details the flexible, rigorous, Evaluative Action Research (EvAR) framework developed to meet the complex demands of the diverse AR projects and the intent to conduct high engagement research evaluation. The EvAR fulfilled multiple overarching needs to: authentically collaborate, engage, and enhance ownership from the ESAR team and the AR project participants and boundary partners evaluated; be informed in decision making via strong reference support; be responsive and flexible yet meet accountability demands to track, demonstrate, and measure process, outcomes, and impacts of projects; use mixed-method data collection to enhance rigor of findings; and utilize a highly reflective and reflexive approach to the evaluation. Many of the latter needs align with underpinning principles and values in AR itself; that is, it is collaborative, consultative, democratic, reflective, reflexive, dialogical, and improvement oriented. Rationale for the framework is provided alongside full details of phases and implementation elements using the ESAR as an example. Throughout the article, features are highlighted that distinguish this new EvAR framework from others. The advantages of adopting a flexible framework, which aims to enhance engagement of those evaluated, are highly relevant to contexts beyond AR if ownership of evaluation outcomes is a goal.