Existing models for parallel programming over Common Object Request Broker Architecture (CORBA) do not address issues specific to parallel programming over a Network of Workstations (NOWs). This paper presents P-CORBA, a model for parallel programming over CORBA that addresses these issues. Transmission and distribution of computing power of a NOW is facilitated by P-CORBA. The main contribution of the work is to bring a notion of concurrency into CORBA. The model illustrates a method for balancing the load on a CORBA-based distributed system. It also provides a new idea for achieving object migration in CORBA. The paper presents detailed performance studies from a prototype of the model that has been implemented. A detailed performance comparison of the model is made with a widely used parallel programming tool, namely Message Passing Interface (MPI). This paper demonstrates that in spite of its overheads, CORBA can be used for parallel programming over a NOW and significant speedups can be obtained.