A network security system and method implements dynamic access control for a protected resource using run-time contextual information. In some embodiments, the network security system and method implements a dynamic access ticket scheme for access control where the access ticket is based on run-time application context. In other embodiments, the network security system and method implements policy enforcement actions in response to detected violations using application programming interface (API) to effectively block detected policy violations without negatively impacting the operation of the application or the user of the application. In some embodiments, the network security system uses enterprise social collaboration tools to interact with the end-user or with the system administrator in the event of detected security incidents.