More than 2,000 Starbucks baristas at 120 U.S. stores have gone on strike since Sunday to protest a new company dress code.

More than 1,000 Starbucks baristas at 75 U.S. stores have gone on strike since Sunday, protesting the coffee giant's new dress code.

Starbucks and the union had temporarily agreed to collective bargaining over dress code changes as part of ongoing negotiations for a new contract. In December, a bargaining session with the company failed to produce better wage gains.