This chapter presents common factors across OECD education systems that contribute to develop success/ul innovative learning environments, as identified from the research literature and from ILE programmes implemented in recent years. Reviewing past experiences in innovative learning environments can help policy makers seeking to design and implement reforms. It defines and reviews the main purposes and contextual features of ILEs, identifies the key elements of successful policy design and explains, through the analysis of past reform experiences, which practices and factors can contribute to efficient policy implementation.