The methods for assessing and predicting the reliability of software, based on a life-cycle approach to software reliability engineering (SRE), are prescribed in this recommended practice. It provides information necessary for the application of software reliability (SR) measurement to a project, lays a foundation for building consistent methods, and establishes the basic principle for collecting the data needed to assess and predict the reliability of software. The recommended practice prescribes how any user can participate in SR assessments and predictions.