James C. Collins and Jerry I. Porras conducted a research project for six years at Stanford University Graduate School of Business. They looked at eighteen outstanding companies that have been successful for a long time and compared each of them to one of their top competitors. They studied these companies from when they first started, when they were medium-sized, and when they became large corporations. The authors wanted to find out what makes these exceptional companies different from their competitors and what common practices these successful companies have followed over time.