1. A method for providing host control of partial trust accessibility comprising the steps of: providing a framework that allows one or more libraries to be identified as partial trust callers enabled to indicate that the one or more libraries could be called from partially trusted code, but not by default; and when a particular library of the one or more libraries identified as partial trust callers enabled is loaded in a process, notifying a hosting application so the hosting application can make a determination on whether or not to allow the particular library to be called by partially trusted code in the process.