The discovery of RNA silencing has greatly expanded the understanding of gene regulation. Present in nearly all Eukaryotes, RNA silencing has emerged as a potent method to regulate gene expression at the transcriptional and post-transcriptional levels. Some of the earliest observations and discoveries associated with RNA silencing were made in plants, and plant research is continuing to further the understanding of RNA silencing in other organisms. The role of RNA silencing in regulating plant development, stress responses, and adaptation is becoming increasing clear. An overview of the various plant RNA silencing pathways and their functions is presented in this chapter, and some of the latest findings in this field will be discussed. Keywords: argonaute (AGO); Dicer-like (DCL); MicroRNA (miRNA); natural antisense small interfering RNA (nat-siRNA); post-transcriptional gene silencing (PTGS); RNA-directed DNA methylation (RdDM); small RNA deep sequencing; RNA-dependent RNA polymerase (RDR); RNA-induced silencing complex (RISC); small interfering RNA (siRNA); small RNA (sRNA); trans-acting small interfering RNA (tasiRNA); transcriptional gene silencing (TGS)