This Case Study is based on a doctoral research project that I conducted in Greek primary education where English was taught as a foreign language. An intervention was employed to explore its impact on the inclusion of English as a foreign language learners with dyslexia and their peers. The discussion herein focuses on the way critical realism as a theoretical framework supported me in exploring the impact of the intervention. Critical realism is a theoretical framework that stands between the realms of positivism and constructivism, having as a central tenet that real world exists but can only be partially apprehended. Implications for employing critical realism to evaluate the impact of educational interventions in the context of inclusive education and beyond are discussed. [This content is provided in the format of an e-book.]