Os Métodos Ageis

COVER FEATURE

Get Ready for

Agile Methods,

with Care

Although many of their advocates consider the agile and plan-driven

software development methods polar opposites, synthesizing the two can

provide developers with a comprehensive spectrum of tools and options.

Barry Boehm aced with the conflicting pressures of accel- I believe that both agile and plan-driven

University of

Southern California

F erated product development and users who

demand that increasingly vital systems be

made ever more dependable, software

development has been thrown into turmoil.

Traditionalists advocate using extensive planning,

codified processes, and rigorous reuse to make

development an efficient and predictable activity

approaches have a responsible center and overin-

terpreting radical fringes. Although each approach

has a home ground of project characteristics within

which it performs very well, and much better than

the other, outside each approach’s home ground, a

combined approach is feasible and preferable.

that gradually matures toward perfection. Mean- THE PLANNING SPECTRUM

while, a new generation of developers cites the We can place various agile and plan-driven devel-

crushing weight of corporate bureaucracy, the rapid opment approaches along a spectrum of increasing

pace of information technology change, and the emphasis on plans, as Figure 1 shows. In this con-

dehumanizing effects of detailed plan-driven devel- text, the term “plan” includes documented process

opment as cause for revolution. In their rallying cry, procedures that involve tasks and milestone plans,

the Manifesto for Agile Software Development and product development strategies that involve

(http://www.agileAlliance.org), and in columns1,2 requirements, designs, and architectural plans.

such as those the “Ongoing Debate” sidebar Compared to unplanned and undisciplined hack-

describes, these developers call for a revitalized ing, agile methods emphasize a fair amount of plan-

approach to development that dispenses with all ning. Their general view, though, places more value

but the essentials. Unsurprisingly, many developers on the planning process than the resulting docu-

who favor plan-driven methods have reacted to the mentation,1 so these methods often appear less

manifesto with scathing criticism. plan-oriented than they really are. Although hard-

Real-world examples argue for and against agile core hackers can use agile principles to claim that

methods. Responding to change has been cited as the work they do is agile, in general these methods

the critical technical success factor in the Internet have criteria, such as Extreme Programming’s 12

browser battle between Microsoft and Netscape. practices, that help determine whether an organi-

But overresponding to change has been cited as the zation is using an agile method or not.

source of many software disasters, such as the $3 Another encouraging trend is that the buzz of

billion overrun of the US Federal Aviation agile methods such as XP is drawing many young

Administration’s Advanced Automation System for programmers away from the cowboy role model

national air traffic control. and toward the more responsible agile methods.

2 Computer 0018-9162/02/$17.00 © 2002 IEEE