In the past decade, the movement to lighter-weight and increasingly agile methods has been the most significant change to affect the software enterprise since the advent of the waterfall model in the 1970s. Originated by a variety of thought and practice leaders and proven in real-world, successful experiments, the methods have proven themselves to deliver outstanding benefits on the “big four” measures: productivity, quality, morale, and time to market.

In the past five years, the methods spread virally. Within the larger enterprise, the initiatives usually started out with individual teams adopting some or all of the practices espoused by the various methods, primarily XP, Scrum, Lean, Kanban (later), and various combinations and variants.

However, as the methods spread to the enterprise level, a number of extensions to the basic agile methods were necessary to address the larger process, organizational, application scope, and governance challenges of the larger enterprise.

Not the least of these is the challenge of agile requirements, which is the necessity to scale the basic, lightweight practices of team agile—product backlogs, user stories, and the like—to the needs of the enterprise’s Program and Portfolio levels. For example, agile development practices introduced, adopted, and extended the XP- originated “user story” as the primary currency for expressing application requirements. The just-in-time application of the user story provided a much leaner approach and helped eliminate many waterfall-like practices, such as imposing overly detailed and constraining requirements specifications on development teams.