The 2012 Homelesssurveywas a continuation of the 2001 survey of the same name, the first national survey of homeless people in a European country. The method for this first survey was based on experiments carried out in the United States since the 1980s. In France, the demand for information on the homeless, who were barely or poorly represented in conventional surveys, increased in the early 1990s. At the initiative of a special working group set up within the CNIS in 1993, pilot surveys carried out by the INED led to the 2001Homelessnational survey, conducted by INSEE. Spain and Italy carried out national surveys thereafter, based on the French example. The 2001 and 2012 Homeless surveys were national representative sample surveys, with a detailed questionnaire distributed by a survey interviewer to homeless people themselves, and more widely to users of aid services. They targetedadults in urban areas with 20,000 inhabitants or more, who spent the night before the survey at an accommodation service or in a place not intended for housing (street, carpark, stairway, etc.), designated as “homeless”. Among them, those who spent the night in a place not intended for housing were referred to as“unsheltered”. In addition to homeless adults and children in urban areas with 20,000 inhabitants or more, the number of homeless people includedthose in rural areas and other urban areas and those included under the national reception scheme for foreigners. The introduction andscopegive the main characteristics of homeless people and changing patterns between 2001 and 2012. The subsequent articles focus respectively on two specific sub-populations: people using French language aid services, who were born in France and taken into careduring their childhood, and French-speaking homeless people with a higher education qualification.