This detailed volume explores newly-developed methods in PIWI-interacting RNAs (piRNAs) research, methods currently applied to other ncRNAs involved in nuclear regulation which can be used to study piRNAs, and piRNA methods applied in non-classical organisms. It also includes several bioinformatic and biophysical methods related to piRNA studies, consistent with the increasing importance of high-throughput sequencing and computational methods. Written for the highly successful Methods in Molecular Biology series, chapters include introductions to their respective topics, lists of the necessary materials, step-by-step, readily reproducible protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and up-to-date, piRNA: Methods and Protocols serves as an ideal guide for researchers seeking to elucidate the numerous mysteries of this area of multicellular biology.