There are a large variety of Procurement Service Providers in the market, and new companies are moving into the market every day.  

Many Procurement Service Providers only offer a "piece" of a solution, such as electronic tools or commerce, or they take over your process, produce some results, and never transfer the knowledge back to your team.  

When selecting a Procurement Service Provider, it is recommended you follow these steps:

• Select an Organization that has a variety of product offerings.  (try to select an organization that offers a combination of tools, consulting, or implementation skills.  This will provide your oganization with the best possible result, as each piece individually does not provide the results that an entire solution can offer)
• Select an Organization that has been established longer than 5 years.  (this may help to eliminate the new consultants that have moved into the market recently and are simply looking to make a profit off of your organization, often at the expense of your vendor relationships)
• Select a Procurement Service Provider that covers a variety of Procurement Product & Service Areas (instead of contracting multiple procurement service providers, find a single provider that has had experience or qualifications to handle all of your target procurement areas.  It is not advisable to hire multiple consulting firms that each specialize in 1 or 2 target areas.  It will be draining on your resources to manage the multiple contacts and projects, and most single product area service providers do not respect your relationship with your vendors)
• Check Reference (Any established Procurement Service Provider should be able to provide you with references that are in some way related to your organization)