SEATTLE - Starbucks will reward customers on Thursday, April 15, with a complimentary brewed coffee if they bring a reusable tumbler to a participating store.

The eco-friendly promotion is part of a sustained effort for Starbucks to partner with its customers in reducing the environmental impact of its products, specifically relating to its paper cup waste. Since 1985, the company has offered customers a price discount for tumbler use.

Starbucks?? goal is to ensure that 100 percent of its cups are reusable or recyclable by 2015, part of its Shared Planet commitment.

"While our cup has become an integral part of the coffeehouse experience over the years, it has also become an environmental concern," said Ben Packard, Starbucks vice president of global responsibility. "As a result, we??ve set aggressive goals to minimize cup waste through recycling and reusable options, and are collaborating with a wide range of stakeholders to drive meaningful change. In addition to working with cup manufacturers, municipalities and recyclers to make our cups more broadly recyclable, we??re encouraging customers to think about reusable cups the way they think about reusable grocery bags."