Post-transcriptional regulation of messenger RNAs (mRNAs) (i.e., mechanisms that control translation, stability, and localisation) is a critical focal point in spatio-temporal regulation of gene expression in response to changes in environmental conditions. The human genome encodes ~2,000 microRNAs (miRNAs), each of which could control the expression of hundreds of protein-coding mRNAs by inducing translational repression and/or promoting mRNA decay. While mRNA degradation is a terminal event, translational repression is reversible and can be employed for rapid response to internal or external cues. Recent years have seen significant progress in our understanding of how miRNAs induce degradation or translational repression of the target mRNAs. Here, we review the recent findings that illustrate the cellular machinery that contributes to miRNA-induced silencing, with a focus on the factors that could influence translational repression vs. decay.