Not too long ago (well, maybe generations ago in computer years), software developers announced a breakthrough: They had come up with a way to let users of word processing programs see on screen exactly what the end result, the printed document, would look like. "What you see is what you get," or WYSIWYG, they called it.

Wouldn't it be a relief if the same were true of inventory reports: that what your computer screen told you was available in the DC, or in transit to the DC, or on its way to customers, was dead-on accurate?

In fact, many of the tools needed to make that happen are already available. Warehouse and transportation management systems, carrier trace and track systems, global positioning systems and the like allow managers to view their inventory in transit from sources in the world's hinterlands to the final customer in the suburbs. And today, any consumer with an Internet connection can follow the progress of an online order from DC to truck to sort center to truck to doorstep in close to real time.

The value of supply chain visibility, however, goes beyond customer satisfaction, as important as that may be. It also enables managers to shift their inventory and transportation modes if needed to respond to changing circumstances.

And more tools are coming. Senior Editor John Johnson, in this month's cover story, looks at how carriers are starting to make use of RFID technology to manage trucks, trailers and their all-important contents.

Unfortunately, as Special Projects Editor Dave Maloney reports in his story on visibility tools, too many companies are failing to take full advantage of what's available, partly out of a close-to-the-vest mentality that leaves them reluctant to share data with vendors and customers. And it has only been recently that visibility tools—other than those supplied to customers by carriers—have become widely available to smaller companies. Integration also remains a big issue. But businesses that don't invest in those tools—and don't work with vendors and customers to extend visibility across networks—are bound to find themselves at a competitive disadvantage.

Some years ago, Yossi Sheffi, director of MIT's Center for Transportation and Logistics, told me that he envisioned the day when a manager of a global supply chain would be able to see his inventory as clearly as a foreman in an old job-shop, who could view a job's progress through his office window. That day is close at hand—but first, you have to open the window.