Abstract
This paper introduces a symposium on Informality to mark the centenary of the International Labour Review (ILR). The symposium brings together ten papers published in the ILR between 1975 and 2016 and devoted exclusively to analysis of informality. It begins with an analytical framework and turns to the origins of the informality discourse. The overview then introduces the papers in the symposium and locates them in the broader literature through illustrative rather than comprehensive referencing. It concludes by looking ahead to what the coming decades of analysis and policy discourse might bring.