A helper service on the user's machine that communicates with the License Server to retrieve licenses. When Houdini starts up on an artist's machine, it connects to hserver running on that machine to ask for a license. hserver then asks the License Server, which may be on a different machine, for a license.

If, for example, a user starts two copies of Houdini FX, only one license will be used by their machine. Hserver acts as a cache, remembering which licenses that machine has checked out and making sure multiple instances of a program will check out only one license.

Only one copy / one version of hserver is ever running at one time on any given machine.

On Windows, this program can be started and stopped in Services as HoudiniServer.