Ninety years ago this month, members of seven small flat janitor unions dared to dream they could build their strength by forming a single organization, the Building Service Employees International Union (BSEIU). A union of mostly immigrant workers, BSEIU was primarily organized by janitors and window washers in its early years - workers who were excluded from other unions at the time. BSEIU faced opposition from building owners, the courts, and even other unions, but managed to quickly grow from 200 members in 1921 to 250,000 by 1960.

From those humble beginnings, BSEIU became SEIU and grew to an organization of 2.2 million janitors, nursing home workers, nurses, child care providers, security officers, county and city workers and other workers. Today SEIU is the fastest-growing union in North America, uniting workers in the United States, Canada and Puerto Rico.

Read more about SEIU's founding as a Union of Janitors.