Processing within a computing environment is facilitated by: determining by a local security manager of a first system in a first security domain whether a local security context of a user is acceptable to a second system in a second security domain; responsive to the user's security context being unacceptable to the second system, creating by a local security manager of the second system a runtime security context for the user in the second system; and providing the first system with a reference to the runtime security context for the user in the second system which is resolvable within the computing environment or a portable representation of the runtime security context for the user in the second system, the reference or the portable representation being subsequently returned to the second system with a request from the first system to process work at the second system.