Committeemen and Committeewomen are typically chosen by voters in a primary election at the local level, such as a ward or township. They serve as members of their party's central committee for a city or county, which then elects members of the state party's committee. The state party members in turn choose the committee members for the national party organizations such as the Democratic National Committee or the Republican National Committee.
On a local level, committeemen and committeewomen are generally responsible for helping to identify party supporters within their jurisdicition and get them to vote at election time. In some older American cities, committeemen and women still have significant influence in distributing patronage jobs to their supporters within city government.