Amazon delivery drivers and Starbucks baristas are on strike in a handful of U.S. cities as they seek to exert pressure on the two major companies to recognize them as unionized employees or to meet demands for an inaugural labor contract.

The Amazon delivery driver strike is nearing its sixth day during the busiest time of the year for last-minute holiday deliveries. The goal is to get Amazon to sit down with the teamsters to negotiate a new contract.

A rolling strike of Starbucks baristas began Friday and grows to include about 300 of the coffee giant's shops across the U.S.