This book analyses the evolution of key Islamist movements and parties in Egypt, Tunisia, and Morocco. It offers a novel and exhaustive study of the evolution of Islamists as shaped by the interplay of domestic, regional, and international factors. Providing an in-depth, theoretically grounded and empirically rich study of political Islam, the volume explores how the overly under-appreciated interaction of domestic, regional and international factors impacts the development of contemporary Islamist actors. By tracing how they adapt and resist to challenging environments within and beyond national boundaries, it charts and explains many of the critical changes and continuities in their organisational set-up, policy choices, ideological leanings, and narratives. Through an inside-out perspective and actor-centered approach, this book aims to overcome the 'compartmentalisation' of the domestic and international spheres as well as the 'obsession' with moderation for Islamists. Specifically, the book chapters address how Islamist actors (re)interpret external events, norms, ideas, and practices from abroad in the light of the constraints and opportunities of their respective domestic environments. At the crossroads of comparative politics, international relations and area studies, it is a key resource for practitioners and scholars interested in party politics, social movements, political Islam and North Africa. The chapters in this book were originally published as a special issue of the journal Contemporary Politics.