GREY2K USA Worldwide is an American non-profit political lobbying organization dedicated to passing stronger greyhound protection laws and ending dog racing.

[3] GREY2K USA was influential in a 2008 local Massachusetts ballot that prohibited greyhound racing in the state.

Afterwards, the organization began similar campaigns against greyhound racing internationally.

[3] The same year, the organization moved from Somerville to larger offices in Arlington.

According to GREY2K USA, there were 49 greyhound tracks when the organization was founded in 2001 and 21 twelve years later.