eXtreme Programming is, as others on this forum have quite rightly pointed out, nothing new. The concepts and principles it embodies have been around for years. The concept is eXtreme simply from the point of view of it advocating code, code, code, instead of locking the developers into the traditional mire of paper and beauracracy.
The key with XP though, as with any other process out there, is not to either accept or whole-heartedly reject everything it says on a whim. Processes are principles, guidelines to follow. Consider them a map of the highlights of some exotic city you plan to visit. Do you throw your entire holiday behind one guidebook, or choose the best bits of a number of them?
eXtreme Programming can add value to projects where little or no process already exists. eXtreme Programming can also add a great deal of value to projects where the process in place is failing badly.
Better yet though, pieces of eXtreme Programming can be mixed and matched with pieces of other processes. Choose the parts that suit you, then go ahead do the same with FDD (Feature Driven Development), Steve McConnell's Best Practice lists and so on.
No one practice is suitable for everyone out there. Mix and match them and build your own. At no point though should any of us be pulled along on some religious crusade to adopt the latest and brightest invention of the coding process gurus.
Just my two cents. ;)
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