Much software research and practice involves ostensible measurements of software, yet little progress has been made on a metrological foundation like the International System of Units (SI) for those measurements since the work of Gray, Hogan, et al. in 1996–2001. Given a physical object, one can determine physical properties using measurement principles and express measured values using standard quantities that have concrete realizations. In contrast, most software metrics are simple counts that are used as indicators of complex, abstract qualities. In this report we revisit software metrology from two directions: first, top down, to establish a theory of software measurement; second, bottom up, to identify specific purposes for which software measurements are needed, quantifiable properties of software, relevant units, and objects of measurement. Although there are structural obstacles to realizing the vision of software metrology that works like physical metrology for all desired measurands, progress is possible if we start with a rational foundation. Why buy a book you can download for free? We print this book so you don’t have to. First you gotta find a good clean (legible) copy and make sure it’s the latest version (not always easy). Some documents found on the web are missing some pages or the image quality is so poor, they are difficult to read. We look over each document carefully and replace poor quality images by going back to the original source document. We proof each document to make sure it’s all there – including all changes. If you find a good copy, you could print it using a network printer you share with 100 other people (typically its either out of paper or toner). If it’s just a 10-page document, no problem, but if it’s 250-pages, you will need to punch 3 holes in all those pages and put it in a 3-ring binder. Takes at least an hour. It’s much more cost-effective to just order the latest version from Amazon.com This book is published by 4th Watch Publishing Co. and includes copyright material. We publish compact, tightly-bound, full-size books (8 ½ by 11 inches), with large text and glossy covers. 4th Watch Publishing Co. is a Service Disabled Veteran-Owned Small Business (SDVOSB). If you like the service we provide, please leave positive review on Amazon.com. Without positive feedback from the community, we may discontinue the service and y’all can go back to printing these books manually yourselves. A full copy of over 300 cybersecurity standards is loaded on our CyberSecurity Standards Library DVD which is available at Amazon.com. For more titles published by 4th Watch Publishing Co., please visit: cybah.webplus.net