The Chlamydomonas Sourcebook, Third Edition, Volume Three: Cell Motility and Behavior has been fully revised and updated to include the wealth of new resources for the Chlamydomonas community.  The book presents the latest advances in the area from an international array of expert authors, reflecting significant advancements in our understanding of the role of basal bodies and flagella in human diseases. In addition, employing quantitative proteomics/mass spectroscopy as well as cryo EM tomography and single particle cryo EM has revolutionized our knowledge of the axoneme in terms of the location of proteins and their interactions. Current insights on mitosis and cytokinesis, flagellar assembly and motility, intraflagellar transport, and more will ensure use of this reference as a guide for understanding human diseases of the cilium.