worldbank.org (17.01.2023) The informal business sector is a source of livelihood for millions of people around the world. Despite its size and importance, business-level data that provide an in-depth understanding and cross-country analysis of the sector are lacking. To fill this gap, the World Bank has collected comprehensive data based on a representative sample of informal businesses using an innovative survey methodology. A recent working paper provides insights on businesses that operate without formal registration. It covers twenty-four cities in seven countries —namely, India, Iraq, the Lao People’s Democratic Republic, Mozambique, Somalia, Zambia, and Zimbabwe— using these publicly available data. Here, we summarize the paper’s key results, focusing on four aspects: salient features of the owners and their businesses; general business practices; performance, and finally, perceptions about registration and reasons for remaining informal.