The DHS occupation categories are based on the major occupation groups in the International Standard Classification of Occupations (ISCO). The major ISCO groups and the occupations that fit within each major group are available at: http:// www.ilo.org/public/english/bureau/stat/isco/isco88/major.htm. However, each country can make modifications based on their own census occupation grouping, the need to incorporate additional occupations that may not be common elsewhere in the world, or other considerations.