Living organisms must constantly balance resources between investment in growth and development on the one hand and defence against biotic and abiotic stress on the other. In eukaryotes, and in plants in particular, RNA silencing plays a major role in this balance by dynamically linking developmental programmes and environmental responses to gene expression changes. RNA silencing is a conserved eukaryotic process mediated by small RNA molecules that inhibits gene expression at the transcriptional or post-transcriptional level through sequence-specific interactions. This phenomenon has been implicated in a large number of biological processes such as genome stability, development or antiviral defense. Although the past decade has witnessed the identification of a large number of RNA silencing factors, yielding our current basic understanding of this conserved process in diverse eukaryotic species, very little is known about their post-translational modifications. However, such modifications are well known to function as molecular switches that regulate the stability or activity of targeted proteins. Based on their sessile lifestyle, it may be even more crucial for plants to develop efficient and potentially reversible ways to control silencing processes. Here, we propose to unravel the post-translational modifications of key RNA silencing factors in plants, characterize their biological function and determine their effect in response to various environmental cues, using a combination of biochemical, genetic and cutting-edge proteomic techniques through both unbiased and targeted approaches. This should provide important novel insights into our understanding of RNA silencing and its regulation in plants and its biological relevance during biotic or abiotic stress responses. This can also offer opportunities to manipulate the various RNA silencing pathways with potential high biotech interest.