For in-house development, companies are experiencing the benefits of agile methodologies as a way to help reduce risk and successfully keep up with the pace of changing business requirements and priorities. Lean Manufacturing  summarizes how these goals are achieved: reduce waste (work efficiently) and reduce inventory (work just in time, produce just enough).
When requirements and business priorities are stable, it is considered prudent to look ahead at up-coming requirements and proactively build flexibility into a
software product in order to cost effectively support future capabilities. However, when priorities and requirements are in a state of flux, it pays off to be more reactive. Any work done beyond the current release horizon could end
up wasted because tomorrow, brand new requirements may replace the ones that were important today.
This is the heart of the philosophy behind agile methods. Extreme Programming (XP)  is one of several agile methodologies, and is a sound strategy for minimizing the amount of work required in order to deliver a high quality,
highly valued software product. XP can be summarized by its four core values: communication, simplicity, feedback, and courage. These values are supported by a set of practices: the planning game, small releases, metaphor, simple design, testing, refactoring, pair programming, collective ownership, continuous
integration, 40 hour week, on-site customer, and coding standards. XP thrives in a software development context consisting of a small, co-located team.
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The Request For Proposal (RFP) process can be agile and efficient. At a high level, the key to achieving this is to specify requirements just in time and containing just enough detail. This paper applies the following XP practices and concepts to the RFP process: acceptance tests, business value, iterative & incremental delivery, onsite customer, pair development, planning game, spike, story, velocity, and yesterday’s weather. In addition, the following concepts are combined with those from XP to achieve maximal benefit: user-goal use case, context diagram, level of detail, and decision tree. The contributions of this paper to the agile community are two-fold: describing a practical application of XP
concepts to a non-programming project; and making use case style requirements processes more agile.