To choose the 100 Best, we conduct the most extensive employee survey in corporate America. More than 81,000 employees from 353 companies responded to a 57-question survey created by the Great Place to Work Institute.

Two-thirds of a company's score is based on the survey, which is sent to a minimum of 400 randomly selected employees. The remaining third is based on our Culture Audit, which includes detailed questions about demographics, pay, and benefits, and open-ended questions on philosophy, communication, etc.

Any company that is at least seven years old with more than 1,000 U.S. employees is eligible. To nominate your company, go to www.greatplacetowork.com. After our evaluations are completed, if news about a company comes to light that may significantly damage employees' faith in management, we may exclude that company from the list.

--Robert Levering and Milton Moskowitz