This chapter investigates the link between informality and growth in Madagascar and aims for a better understanding of the informal sector. It provides an analysis of the characteristics of informal production units and informal employment. Findings suggest that informality is a key feature of economic activity in Madagascar, and that informal production units are the main driver of employment with a deep concentration around self-employment. Overall, informality is associated with a lack of awareness of administrative procedures and the complexity and cost of tax and regulatory measures. The informal sector’s Total Factor Productivity (TFP) growth is more stable and higher on average than the formal sector TFP.