 The responsibility for operating and maintaining water and sanitation services rests with 19 provincial water and sewer companies, more than 100 municipalities and more than 950 cooperatives, the latter operating primarily in small towns.Among the largest water and sewer companies are Agua y Saneamientos Argentinos (AYSA) and Aguas Bonarenses S.A. (ABSA), both operating in Greater Buenos Aires, Aguas Provinciales de Santa Fe, and Aguas Cordobesas SA, all of them now publicly owned.In 2008 there were still a few private concessions, such as Aguas de Salta SA, which is majority-owned by Argentine investors, and Obras Sanitarias de Mendoza (OSM).