How do they do it? See books:
- TheTwelveSimpleSecretsOfMicrosoftManagement by David Thielen.
- MicrosoftSecrets: How the World's Most Powerful Software Company Creates Technology, Shapes Markets, and Manages People.
- SteveMcConnell's books (at http://www.construx.com/stevemcc/books.htm), including SoftwareProjectSurvivalGuide, CodeComplete, RapidDevelopment and AfterTheGoldRush.
- DebuggingTheDevelopmentProcess
- DynamicsOfSoftwareDevelopment
- RenegadeOfTheEmpire
- WritingSolidCode
- ShowStopper
(With so many books, it must not be that much of a "secret" any more! ;-)