This special PJLIR issue offers critical reflections on important core and functional areas of the informal sector; it draws upon evidence needed in informed decision making. Hence, this collection of papers embraces a variety of disciplinary approaches and levels of analysis, a diversity that captures the multiple facets and determinants of the informal economy.  Some studies analyze the practice of social responsibility at the national or policy level, while others focus on specific concerns such as safety and health, housing, cooperatives and retailing. This 'embeddedness' of the informal sector to the formal economy explains the apparent paradox that, in an age of global economic integration, national differences in economic institutions become even more apparent and consequential. These studies make clear, the determinants of change and development include not only market incentives but institutional and strategic factors as well.