This volume provides the reader with step–by–step methods to study plant ARGONAUTE (AGO) functions. Chapters in Plant Argonaute Poteins: Methods and Protocols summarize the main biochemical, molecular and cytological methods to study AGO–small RNA complexes and their interactions with target RNAs, AGO subcellular localization, AGO association with polysomes, AGO role in meiosis and DNA repair, methods for the identification, cloning and characterization of AGO genes in different plant species, and non–radioactive protocols for small RNA detection. Finally, a series of chapters describing computational methods to study plant AGO function and evolution are provided. 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 troubleshootingand avoiding known pitfalls. Authoritative and practical, Plant Argonaute Proteins: Methods and Protocols aims to deliver the most complete and updated list of protocols to study plant AGO function.