Future industrial production and engineering environments will profit substantially from emerging open distributed computer communication network environments. They will, in principle, be able to benefit from a high potential of services available in such environments to support individual client applications. In practice, however, free and flexible client/server cooperations are frequently hindered by the great and confusing variety of interfaces involved in accessing various and heterogeneous network services. In order to support open client/server cooperations in distributed systems, this contribution proposes a unifying description mechanism for remote services in computer networks. It describes an application oriented generic ommunication service, which facilitates client/server cooperation in open systems. Most important basis for such a service is a uniform service specification mechanism for open server interfaces. Correspondingly, the paper first specifies a specific service interface description language (SIDL). It then shows how such a service interface description could also be used for automatic creation of serverspecific local human user interfaces. In combination, a generic network interface description language (NIDL) specification, as proposed here, supports client applications in open systems by providing a common mechanism to access and utilize any service available anywhere in the network.