The informal sector is typicallycharacterized as being very heterogeneous and possiblycomposed of two clearly distinct segments, sometimes calledthe lower and upper tier. However, empirical evidence showsthat even among lower tier entrepreneur's profitabilitycan be quite high. The authors combine these findings anddevelop an innovative approach to identify what is calledconstrained gazelles, next to the well-known survivalists inthe lower tier and growth-oriented top-performers in theupper tier. The sample of informal entrepreneurs in sevenWest-African countries allows linking the relative size ofthese three groups to the structural and macroeconomicenvironment in these countries.