The ultimate goal of a programming environment is to help simplify the software development process. For an object-oriented language, a visual (object-oriented) programming environment (VOOPE) must at least satisfy four essential requirements to meet this goal: interactivity, integration, incrementality, and intelligence. In this study, object-oriented techniques were systematically applied to construct such a VOOPE. On the other hand, some characteristics of object-oriented languages, such as inheritance and polymorphism, may themselves be barriers to understanding, maintaining and even constructing object-oriented programs. To solve, or at least alleviate, this problem, a language-based editing process has been designed and incorporated into our VOOPE. This process contains two key elements: syntax-directed editing facilities and an in-place editing assistant, which facilitate object-oriented program development by providing useful programming guidance and by reducing the number of potential programming errors. We have so far developed a window-based environment prototype using Visual C++ and the Microsoft Foundation Classes library.