A system that includes multiple hosts, each running a plurality of virtual machines. The system may be, for example, a cloud computing environment in which there are services and a service coordination system that communicates with the hosts and with the services. The services include a middleware management service that is configured to maintain per-tenant middleware policy for each of multiple tenants. The middleware management service causes the middleware policy to be applied to network traffic by directing network traffic to a middleware enforcement mechanism. This middleware policy is per-tenant in that it depends on an identity of a tenant.