There are some low-cost providers, but they haven't made a major impact on the market, says Barnes. "You know the old adage, 'no one got fired for hiring IBM'? It's the same thing for WMS. There's a handful of core companies that do it and do it well, and they're [frequently] getting the nod," he says.

Even when buyers choose a lower-cost provider, they often cite functionality or technology requirements as the main reason for their choice. "If we had seen something else that would have provided a great deal more value, then I think we might have gone for it. But to be honest, when we looked at our needs, Radio Beacon seemed to fill all of them and at a cost that was significantly less," says Sports Giant's Simkin.

If you buy a WMS based on price, give equal weight to the vendor's financial viability. Heim tells of several former customers that selected a vendor based on price. "Now that company is out of business, and they're out a fair amount of money," he says.

Even more common is what happened to Sargento Foods. The manufacturer watched as another company bought its original WMS provider and then failed to continue investing in the product. When it came time for Sargento to replace its WMS, potential vendors' financial viability became a key consideration, says Roehrborn.

Before you even approach a WMS provider, you need to have a solid understanding of your own operations. Often this will require mapping your warehouse operations so you can provide potential vendors with an outline of your business flows.

While such maps can be very helpful, there are dangers in sticking to them too closely. "You could run the risk of mapping what could be a bad process," says Heim. "So while it is very important to understand your business, you also want to allow for some flexibility to change your practices and gain more efficiencies."

This is especially true for companies that are implementing a WMS for the first time. Consider the case of Kirkland's: While the retailer was selecting a WMS, it also was consolidating from three facilities into one and introducing new conveyor and sortation systems. Mapping processes in a yet-to-be-opened facility would have been impossible. Instead, the company gave its potential vendors a document showing what the processes might be, then considered the solutions' scalability and flexibility, says Weier.

Finally, don't focus entirely on your operational needs. You also need to take into consideration your company's broader vision and strategic direction, recommends RedPrairie's Kozenski. "You can expect that when you buy a WMS today, it is going to last you a good ten to fifteen years," he says. "It's realistic to think that way. Therefore, understanding what logistics means to your company and where it is going is very important."