This chapter discusses the Object-Oriented and Component-Based Middleware. In the object-oriented paradigm, of course, data and procedure calls are encapsulated inside an object. One of the best known early technologies was Common Object Request Broker Architecture (CORBA) which dates back to 1991. As the 1990s progressed, other object-oriented middlewares arose. Another well-known middleware was, or still is Microsoft's Distributed Component Object Model (DCOM). In the early 2000s, when Microsoft brought out their.NET framework, they also brought out.NET Remoting, which was intended to solve some of the problems originally experienced by DCOM. Both CORBA and.NET Remoting are intended to handle client-side issues as well as server-side issues such as persistence, object lifetime, etc. In the late 1990s, Enterprise Java Beans (EJBs) was developed, primarily by Sun Microsystems. EJBs are primarily targeted toward server-side issues such as persistence and object lifetime, although considerable client-side processing is also included.