As the requirements for system analysis and design become more complex, the need for a natural, yet formal way of specifying system analysis findings and design decisions are becoming more pressing. We propose the Object-Process Language as a textual natural language means for systems specification that is complementary to the graphic description through Object-Process Diagrams. 1 Natural Languages and Graphic Representations of Systems As the complexity of computer-based systems grows, precise and concise specification is in increasing demand, calling for new approaches of systems development. One very common and powerful modeling technique is simple prose, or natural language. Natural languages are very powerful because they are the result of thousands of years of evolution, during which humans who use them have developed the ability to make subtle observations and distinctions, such as those made in this sentence. However, natural languages are also frequently ambiguous and always l...