MarketSource is a sales and marketing company headquartered in Indianapolis, Indiana. The company provides outsourced sales and marketing services to businesses in a variety of industries, including technology, telecommunications, and consumer electronics. MarketSource's services include sales training, product demonstrations, and lead generation. The company was founded in 1975 and has grown to become one of the largest sales and marketing companies in the United States. MarketSource has over 7,000 employees and operates in all 50 states.