One of the WalkerRoyce top 10 SoftwareManagementPrinciples.

"Establish an iterative life-cycle process that confronts risk early.  A more dynamic planning framework supported by an iterative process results in better risk management and more predictable performance.  Resolving the critical issues first results in a more predictable construction phase with no surprises, as well as minimal exposure to sources of cost and schedule unpredictability."

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Care to name an IterativeDevelopment methodology?
''(Say, ExtremeProgramming?  ;-)''