FRM (Facility Resource Management) and FMS (Field Management System) focus on different scopes of service operations.
FMS systems are designed to manage field activities.
They focus on organizing on-site work: task assignments, routes, technician actions, and field reporting.
FRM systems are designed to manage all that FMS does plus the entire resource and operational layer behind field work — assets, materials, documentation, lifecycle history, and collaboration between service providers and clients.