Marriott International

Marriott International is a worldwide operator and franchisor of hotels and lodging facilities. Headquartered in Bethesda, the company ranked 213 on the Fortune 500 list and earned $10,908.0 million in revenue, according to CNNMoney.com.

AP

Black and Decker

Black & Decker (now Stanley Black & Decker) is a designer and importer of power tools and home appliances. Headquartered in Towson, the company ranked 435 on Fortune 500 list and earned $4,775.1 million in revenue in 2010, according to CNNMoney.com.

AP

Constellation Energy

Constellation Energy is a leading supplier of energy products and services to wholesale and retail electric and natural gas customers. It is headquartered in Baltimore. The company ranked 149 on Fortune 500 lists and made $ 15,598.8 million in revenue in 2010, according to CNNMoney.com.

(AP Photo/Gail Burton)

Host Hotels and Resorts

Host Hotels & Resorts Inc. is recognized as the premier hospitality real estate company through aggressive asset management and disciplined capital allocation. Located in Bethesda, the company ranked 492 on the Fortune 500 list and made $4,216.0 million in revenue in 2010, according to CNNMoney.com.

(PRNewsFoto/Host Hotels & Resorts, Inc.)

Lockheed Martin

Lockheed Martin, located in Bethesda, is the U.S. government's largest defense contractor. In 2010, it grossed $45,189.0 million in revenue and ranked 44 on the Fortune 500 ranks, according to CNNMoney.com.

(PRNewsFoto/AgustaWestland North America)