Women who were discriminated against in terms of rights to citizenship, property ownership, and access to work nonetheless played a key role in the early modern underground economy that was never completely separated from the rising market economy. The aim of this chapter is to explore female involvement in a wide range of illicit economic activities: from survival strategies for the poor to criminal activities such as smuggling. From this perspective, it concentrates on Lyon’s textile trades, a highly feminised sector in the eighteenth century. At a time of strong demographic and economic expansion, women took advantage of the demand for consumer and luxury goods, especially in the garment sector, to find a niche for themselves in the cloth trades, in both licit and illicit ways. As elsewhere in Europe, the presence of guilds had a significant impact, both positive and negative, on the opportunities available to women. In March 1673 a royal edict required all unincorporated trades to form guilds. In several French cities, due to this Women’s illicit economic practices in Lyon193 reform, it was possible for women to create guilds in ‘feminine’ trades or to become members of mixed guilds