-Development of lightweight methodologies- a reaction to:

• Ponderous use of waterfall process

• Non-intuitive, difficult-to-use CASE [Computer-Aided Software Engineering] Tools 

• Capability Maturity Model (done for Dept. of Defense by CMU's Software Engineering Institute)

• "Heavy" application of Rational Unified Process (?)

-Great deal in common among "Light" group, many now united in identification "Agile"

• "Manifesto for Agile Software Development"- Statement of common values and principles

• Agile Modeling - Web site amplifying message (Scott Ambler)

• All methods stress importance of handling changing requirements, inability to predict before coding begins

• Software design should be flexible & adaptive