With 1.8 million members, the largest service one of these organizations in North America is the SEIU
[DOC] [TLE] Service Employees International Union - Wikipedia [PAR] Service Employees International Union (SEIU) is a labor union representing 
almost 1.9 million .... One of the major potential areas of union growth in the 
United States is ... SEIU's largest local union, 1199SEIU United Healthcare 
Workers East has a .... paying agency fees, compared to about 1.8 million regular 
members.