Starbucks' close competitors include other specialty coffee shops, doughnut shops, and restaurants.
Starbucks holds a dominant position in the specialty coffeehouse market and has no single clear rival in the sector. (Its closest specialty coffeehouse competitor is Caribou Coffee, with 415 stores in the US--less than 5% of Starbucks' 11,000-plus). Its most intense specialty coffeehouse competition is dispersed among the thousands of independent or small-chain coffee shops around the nation and the world.
The National Coffee Association estimates that the US coffee market will reach $29 billion in 2011 [10], and the markets the two competitors target are different. The former aims at the cheaper coffee to go, whereas the latter aims at providing a premium experience for a luxury price. McDonald's larger retail footprint may overlap more with Starbucks' core markets, but their stark differences as stores are reflective of the general differences between their core customers.
Privately owned Dunkin Donuts is another major competitor, with nearly 5,000 stores in the U.S. Although Dunkin' Donuts' retail footprint also overlaps largely with that of Starbucks, their customer experience is much more similar to the coffee-to-go model rather than the "third place to work and relax" model. Consequently, they are likely to compete more directly with McDonald's than with Starbucks.