A new generation of developers cites the crushing weight of corporate bureaucracy, the rapid pace of information technology change, and the dehumanizing effects of detailed plan-driven development as cause for revolution. In their rallying cry, the Manifesto for Agile Software Development, these developers call for a revitalized approach to development that dispenses with all but the essentials. Real-world examples argue for and against agile methods. Responding to change has been cited as the critical technical success factor in the Internet browser battle between Microsoft and Netscape. But overresponding to change has been cited as the source of many software disasters, such as the $3 billion overrun of the US Federal Aviation Administration's Advanced Automation System for national air traffic control. The author believes that both agile and plan-driven approaches have a responsible center and overinterpreting radical fringes. Agile and plan-driven methods both form part of the planning spectrum. Thus, while each approach has a home ground within which it performs very well, and much better than the other, a combined approach is feasible and preferable in some circumstances.