Interesting. In April 2002, following the publication of two DoD directives that established a preference for evolutionary acquisition, the U.S. Under Secretary of Defense issued a 3 page memorandum (pdf) to explain the term evolutionary acquisition:
Evolutionary Acquisition:
An acquisition strategy that defines, develops, produces or acquires, and fields an initial hardware or software increment (or block) of operational capability. It is based on technologies demonstrated in relevant environments, time-phased requirements, and demonstrated manufacturing or software deployment capabilities. These capabilities can be provided in a shorter period of time, followed by subsequent increments of capability over time that accommodate improved technology and allow for full and adaptable systems over time. Each increment will meet a militarily useful capability specified by the user (i.e., at least the thresholds set by the user for that increment); however, the first increment may represent only 60% to 80% of the desired final capability.
There are two basic approaches to evolutionary acquisition. In one approach the ultimate functionality can be defined at the beginning of the program, with the content of each deployable increment determined by the maturation of key technologies. In the second approach the ultimate functionality cannot be defined at the beginning of the program, and each increment of capability is defined by the maturation of the technologies matched with the evolving needs of the user.
If it’s good enough for the DoD to do incremental development to cope with evolving requirements, then it is good enough for me.
[via Tom Gilb’s excellent, but challenging, Competitive Engineering. If you wanna legite FREE e-copy then email me and I’ll tell you how to get one].
