This fourth edition was prepared in 2015-2016 as a supplementary text for a graduate music cataloging course. This edition is rewritten to a large extent to conform to the new instructions and paradigms represented in Resource Description and Access (RDA). RDA instructions for printed music, recorded music and music video are accompanied by advice, examples, illustrations and complete catalog records, including versions in MARC21 format. Consistent with RDA, the chapter on form and choice of access points found in earlier editions is gone, replaced with a chapter on authorized access points. The concept of "uniform title" has evolved into the concept of the "preferred title," as part of an authorized access point, which might require manipulation and addition of some elements for disambiguation and collocation. Only three chapters are used for description of printed music, sound recordings and video recordings. Many of the older LP examples were removed as were VHS video recordings. Multimedia packages are now rare in the marketplace, but streaming audio and video are quite evident so examples now include those media. Facsimile examples from the third edition have been retained and many new examples have been added. Most catalogers today are using RDA in combination with MARC21. Accordingly, in an appendix, we have rendered each example in MARC21 format using the OCLC Connexion approach to MARC21 record formatting.A lengthy bibliography in earlier editions has been replaced by a brief list in the introduction, with pointers to online resources that are both current and constantly updated by working catalogers.