What will your IT department look like in, say, five years? This is an important question, because we're at the beginning of an array of major changes in the how, where and why IT is done.

These changes are being driven by a number of powerful technical and market forces that include virtualization, software-as-a-service, an increasingly mobile and decentralized workforce and the demand for IT organizations to add value rather than simply provide services.

Every one of these forces is creating a challenge in which change is inevitable. Being able to recognize when these challenges are on your horizon and respond to the implicit call to action are what will distinguish the organizations that can capitalize on a competitive edge.

And let's be clear, when we talk about competitive edge we're almost always talking about a short-term tactical advantage -- there are few situations in which a competitive edge has durable, strategic value. The art of staying competitive is about being able to continually adjust and take advantage of changing circumstances.

If the IT organization is to add value, it must have a productive stake in the business process. To put that another way, IT has to be able to show that it delivers a real return on investment. Of course, you know that to be true, so the problem is how to make that a fact rather than a theory.

First, consider the combination of low-cost hosting (compared with owning, managing and maintaining server infrastructure) and virtualized infrastructure, such as 3tera's AppLogic. This makes the argument for running any customer-facing functions, such as Web services, applications and extranets, in-house much less compelling, if not downright specious.

The next challenge is whether you need to run your own enterprise applications in-house. A few years ago software-as-a-service was experimental. Things have changed, and as the software-as-a-service vendors have become more sophisticated and the Internet infrastructure more robust, the value proposition has become undeniable. And now that inexpensive, fat data pipes are available, user-access performance is not much of an issue.

Those mobile and remote office staff provide the next challenge. Software-as-a-service provides a more cost-effective way of delivering core business-process support to wherever your users are compared with running those applications in-house on hardware you own and manage, and then having to run VPNs through the enterprise's envelope to provide secure access.

The result of these last two opportunities is that services such as Salesforce, NetSuite, Webex and CrownPeak are becoming major forces in delivering enterprise business resources. This is not only because they are cost effective, but also because they simplify the enterprise IT landscape in much the same way that adopting outsourced virtualized infrastructure for customer-facing IT operations does.

What could the IT department of tomorrow look like? In many organizations everything customer facing will be hosted externally on scalable virtualized infrastructures and enterprise applications of all kinds will be services provided by software-as-a-service vendors. Internal technical staff will exist primarily to enable, manage, and secure user access and data resources on user computing devices on a simpler network that will exist primarily to connect users to outsourced applications and services.

The biggest benefits of this new IT will be flexibility and scalability. And when it comes to the drivers of enterprise IT there will be less focus on the mechanics of providing IT services and more on the business of the enterprise. Indeed, ultimately, IT will be inseparable from the enterprise, and most of its responsibilities will involve managing services with quantifiable ROI.