Of course, such results are more likely to materialize when the procurement or spend-management solution that it chooses best fits the organization's needs. A starting point for that is determining the business problems you're trying to solve, says Mickey North Rizza, research director with . Is your goal to streamline the payment process? Reduce spending with unauthorized vendors? The area(s) in which you need to focus should drive the solution. "The biggest mistake is that companies don't understand what business problem they're trying to solve," North Rizza says.

Another decision concerns whether to go with a software-as-a-service (SaaS) solution, in which the vendor hosts the system, or to host the system yourself. When an organization outsources the hosting and management of a technology solution, it gains flexibility, says Elka Popova, North American program director of the unified communications and collaboration practice with Frost & Sullivan. It doesn't have to dedicate its own resources -- both employee and IT -- to the day-to-day management and maintenance of the systems. These solutions also can be effective for organizations with geographically distributed locations, as it's often not cost-effective to install a solution within each site. In addition, it's usually easier to scale up and down as business changes with a SaaS solution than with an installed one.

While the advantages of SaaS solutions are compelling, they aren't always are the answer, Popova notes. Larger businesses often have more complex IT environments, and few systems operate in isolation. "If you deploy a premises-based system, it can be easier to integrate and customize it." In addition, on-site systems typically allow for greater control.

Another decision: whether to go with a boutique solution that focuses on one segment of the procure-to-pay function, or a system that is more all-encompassing, says Constantine Limberakis, senior research analyst in global supply with Aberdeen Group. Some companies offer solutions that span the overall procurement function -- managing supplier relationships, tracking contracts, invoicing, and so one -- while others address one component of the process. Still other vendors have developed systems geared to specific verticals. "It ultimately comes down to the main purpose of the product," Limberakis says. "What's the process you're trying to address?"