In reality, many companies, including household product manufacturer Sunbeam Products, Cott beverage company and Nexcom, a $2 billion mass merchant that supplies the U.S. Navy with everything from clothes to the products that clean them, are forced to run multiple WMSs, either because they’ve acquired companies that deploy different packages themselves or because decentralized business models give their various warehouses the liberty to decide which WMS is right for them.

"The vanilla-flavored world where all systems are the same just isn’t an immediate reality for a company like Cott that’s growing very rapidly through acquisitions and organic growth," says Douglas Neary, CIO of the Toronto-based company.

Running more than one WMS causes headaches. Make that migraines. Ed Janowsky, vice president of information technology at Sunbeam in Boca Raton, Fla., says that running two WMSs in 12 warehouses compromises his company’s efficiency and drives up its operational costs. "You have a duplication of software licensing and maintenance fees," among other expenses, he says.

Mitch Long, Janowsky’s director of IT applications, says that running two different WMSs puts pressure on the IT staff at Sunbeam because they have to write additional interfaces between the company’s two WMSs and its back-end systems. "We need multiple people with different skill sets to support those products," says Long.

In addition, running multiple WMSs can lengthen a company’s fulfillment cycle, according to Anthony Venuti, vice president of CDM, a consulting company based in Cambridge, Mass. Also, Long says, Sunbeam’s inventory accuracy varies because it is running multiple WMSs. And if the WMSs are not well integrated with the order processing system, orders can get lost because there’s no consistency as to how orders are fulfilled and how the facilities are run, says Venuti. To top it all off, when you’re not running a common WMS across distribution centers, it’s harder to move warehouse employees from one location to another because every time you do you need to train them on a foreign system. Businesses also miss out on the benefits of shared methodologies and best practices for using the system and for running the warehouse.

But despite those problems (or, rather, because of them), Cott, Nexcom and Sunbeam have developed best practices to mitigate the cost and disadvantages of running multiple, unintegrated warehouse systems.

To guard against errors, Cott’s Neary compares information across his company’s three warehouse management systems and two ERP systems, and conducts hand counts of the finished goods to ensure that the inventory data is consistent. And, where possible, he writes interfaces between his WMSs and his ERP systems so that the two can share information without the need to enter data manually.