Like hemlines and lapel widths, modes of IT organization have swung in and out of fashion over time. These days, consolidation is the favored style. Among state CIOs, for example, consolidating IT activities for the enterprise is the No. 1 management priority for 2009, according to a survey conducted last year by the National Association of State Chief Information Officers (NASCIO).

"We've seen a general direction toward a higher degree of consolidation, even to centralization, for the last five years," said Doug Robinson, NASCIO's executive director.

Under consolidation, one IT department serves the whole government, charging agencies for services they use. In this model, agencies usually retain their own IT budgets. Under a centralized model, the IT department controls budget dollars.

While consolidation might be all the rage today, developing an enterprise approach to government IT isn't easy. Consolidation initiatives often meet resistance from agencies. Support might wax and wane depending on the current governor, mayor or county executive. And consolidation will succeed only if the IT department running the show is up to the task.

"If you're going to have a central shop providing enterprise services, it better be good. It better be secure. It better be cost-effective. It better be well managed," said Richard McKinney, former CIO of the Metropolitan Government of Nashville, Tenn., and Davidson County.

According to McKinney, who currently serves at infrastructure optimization adviser for Microsoft Public Sector, the last time centralized or consolidated models were in vogue was in the mainframe era, when one large machine provided all of a government's computing power.

Agency officials weren't crazy about that model, McKinney said. "People didn't like that the central shop tried to dictate to everybody how they were going to use the information technology." So when vendors came calling with midrange computers loaded with software for vertical applications, agencies were ripe for change. "Toward the end of the 1980s, government had almost completely gone from being centralized to decentralized," he said.

Then came PCs, networks, servers and the Internet. Suddenly governments found themselves with an unruly proliferation of IT systems, multiple e-mail systems, multiple local area networks and few ideas about how to tie them together. "People began to look at the decentralized model and say, 'This doesn't work very well.' It's really wasteful, it's hard to manage,'" McKinney said. It was also hard to secure. "So people began to talk again about IT consolidation."

Why Consolidation?

Several forces have combined to make consolidation the favored model today, said William Bott, consulting partner at the Change and Innovation Agency in Kansas City, Mo., and former deputy CIO of Missouri. For one thing, it offers economies of scale as governments seek to replace aging IT infrastructure, rein in costs and eliminate redundant functions and systems.

Technology also is driving the trend. "You have an unprecedented time in IT history where a lot of things are playing nicely together that never did before," Bott said. Now that IT systems running on disparate platforms can share data smoothly, it's easier to take an enterprise approach.

From a third perspective, legislators and government executives want to boost IT security and encourage data sharing, Bott said. They see consolidation as a way to enforce standards that safeguard IT systems and still allow information to flow across the enterprise.

Politics also play a role. "There's been a desire on the part of elected officials to try to get control of IT," said David McClure, managing vice president of Gartner Government Research. When large IT projects go awry, critics call for greater discipline and more standards. To many elected