Zuse's textbook on software measurement provides basic principles as well as theoretical and practical guidelines for the use of numerous kinds of software measures. It is written to enable scientists, teachers, practit ioners, and students to define the basic terminology of Software Measurement and to contribute to theory building. The textbook considers, among other, qualitative and numerical models behind software measures. It explains step-by-step the importance of qualitative properties, the meaning of scale types, the foundations of the validation of measures, and the foundations of prediction models, the models behind the Function-Point method and the COCOMO model, and the qualitative assumption of object-oriented measures. For applications of software measures in practice more than two hundred software measures of the software life-cycle are described in detail (object-oriented measures included). The enclosed CD contains a selection of more than 1,600 references of literature, and a small demo version of ZD-MIS (Zuse/Drabe - Measurement Information System) is presented.