(from Management Service Provider
A company that monitors the network performance, website statistics, etc. of an e-commerce business. MSPs are often best suited to bricks and mortar companies that are not interested in hiring a huge e-commerce department, but also don't want to just colocate a few servers and hope for the best.
As an application service provider (ASP) lets you use computer applications without worrying about keeping software updated and virus-free, a management service provider lets you get your business online and keep it running without worrying about redundancy, connectivity, usability and logistics.
I spotted this term in the October 2, 2000 issue of Information Week, but it has undoubtedly been around for at least several months before that date.