This comes on the heels of my posting yesterday about the need to do one thing well.
Some folks from Havard say you have to do four things well and two of four additional things well. What Really Works: The 4+2 Formula for Sustained Business Success came out in May 2003. Under their equation, you must instill a strong sense of strategy, execution, culture, and organization. You also have to do two of the following four well: acquire talent, develop leadership, foster innovation, or grow successfully through M&A. They also say they have research to back it all up.
The August issue of Inc. Magazine has a slightly longer review of the book.