Ask for redundancy Choose a company that has prepared for an emergency by investing in redundancies, suggests Don Briggs, who operates Advanced Communications Technology, a hosting service and network designer based in Dexter, Missouri.

Insist on quality Make sure your provider offers quality of service, which is a technical term that refers to a protocol that gives priority to voice packets over data packets. Sound quality and customer service vary widely among providers, and undercapitalized carriers often seek ways to cut corners.

Focus on the metrics "Uptime," the percentage of time the network is running, is important, says consultant Tom Wales. So is bandwidth. "Make sure that they're providing at least 64 kilobits per second for each voice conversation," he notes. "They'll say you need less, but that's the least you should have."

Get it in writing Wales recommends requiring hosts to address these issues in a "service-level agreement" that consummates your telecom deal. If nothing else, says Lundin, take advantage of the 30-day free trial that many companies offer. "You try it out, and if it works, then go with it."