Headquarters: McLean, VA, USA
2010 Revenue ($ millions): 30,000
Rank: 19

What makes it so great?

Known by the masses for its color-coated chocolates, Mars employees know it more for its special culture. "It is a very warm, welcoming culture where good work is recognized and rewarded," says one. CEO Paul Michaels doesn't have a private office or a reserved parking space; most office spaces have open plans, breaking down physical and psychological barriers by making everyone approachable.

Globally, the company has run an associate engagement program since 2003. Some of these communication initiatives include Q&A sessions, suggestion boxes in the offices, or "site involvement teams," which allow associate representatives of various divisions to make recommendations to management.

Last updated October 28 2011: 4:50 PM ET