The chapter examines the design of simulation games as models of reality, focusing on their effectiveness for learning, transfer and organisational transformation. This transfer is facilitated through two main approaches: ‘design-in-the-small’ (DIS), which involves crafting games to model specific systems structures and processes, and ‘design-in-the-large’ (DIL), which leverages these games to drive systemic changes in organisations. A key component in achieving real-world impact is the debriefing and evaluation process, where participants reflect on game experiences and draw parallels to their organisational settings. Through this reflection, players can translate their insights into actionable strategies for their own work environments. A combined summative and formative evaluation process fosters both individual skill development and collective organisational learning, supporting sustainable change and adaptation in complex, dynamic environments. The chapter describes the interconnections of DIS and DIL for generating transfer, transformation and organisational results through gaming simulation.