Yes. It does. For a short time you will have no music on your device. You will panic, At least I did. All my music was gone, well not gone, it was still listed, just grayed out, so I couldn't play anything, but eventually all my songs, okay, 90% of my songs were either matched, or uploaded, and available to be played, and I had a couple more gigs of free space on my iphone. After all, that is the point of Itunes match, right? Store your music in the cloud, so you don't have to store it on you ios device?