What exactly does the concept of agility refer to?
Agile IT project management methods

Today's IT companies face intense pressure and tough competition in a market characterized by diverse technological offerings, unstable demands and short delivery times. Ex ante planning and organization of the IT development process is proving difficult to achieve these days.

Applied to the world of software, the notion of agility refers to the ability of IT companies to adapt to evolving customer demands, most often arriving during the course of a project, and to better control the "cost/quality/functional scope" triptych. Agile" methods represent a new approach to IT project development, described as iterative, incremental, encouraging self-organization and adaptation to change.