ApplicationSecurityManager.DetermineApplicationTrust(ActivationContext, TrustManagerContext) uses the configured ApplicationSecurityManager.ApplicationTrustManager property to determine whether to allow execution of the specified application with the permission set requested in the application manifest. The trust manager's behavior is dependent on the trust manager implementation and the information passed in the context parameter. The default behavior of the trust manager is to establish a user interface (UI) dialog box to determine the user's approval. However, a trust manager can also determine an application's trust status based on other criteria, such as decisions provided by a corporate database. The trust decision can be persisted, depending upon the context parameters properties and the trust manager implementation. If the trust for the application is persisted for a decision based on a user dialog box, future calls to the System.Security.Policy.ApplicationSecurityManager will not present the UI dialog box for every request for that application. ApplicationSecurityManager.DetermineApplicationTrust(ActivationContext, TrustManagerContext) is called after the manifest, but before the application has been downloaded to the local system.