Plant Endosomes: Methods and Protocols explores a collection of protocols and techniques to analyze in vivo trafficking of endocytic/endosomal cargo, including lipids, fluids, proteins and ligands, ultrastructural features of endosomes by high-pressure freezing/freeze-substitution and electron tomography, as well as protein-protein interactions in the endosomal and endomembrane system. The volume continues with coverage of the sorting defects in the transport of vacuolar storage proteins, function conservation of plant endosomal proteins, endosomal trafficking during plant responses to pathogens, protein composition of endosomes and endocytic vesicles, ubiquitination of endosomal cargo proteins and the identification of novel endosomal components by chemical genomics and proteomics. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols and tips on troubleshooting and avoiding known pitfalls. Detailed and practical, Plant Endosomes: Methods and Protocols gathers contributions from many leading and emerging plant membrane trafficking researchers in order to promote and facilitate novel studies and ideas in this vital field.