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AbstracttRNA biogenesis in yeast involves the synthesis of the initial transcript by RNA polymerase III followed by processing and controlled degradation in both the nucleus and the cytoplasm. A vast landscape of regulatory elements controlling tRNA stability in yeast has emerged from recent studies. Diverse pathways of tRNA maturation generate multiple stable and unstable intermediates. A significant impact on tRNA stability is exerted by a variety of nucleotide modifications. Pre-tRNAs are targets of exosome-dependent surveillance in the nucleus. Some tRNAs that are hypomodified or bear specific destabilising mutations are directed to the rapid tRNA decay (RTD) pathway leading to 5'-3' exonucleolytic degradation by Rat1 and Xrn1. Some tRNA molecules are marked for degradation by a double CCA at their 3' ends. In addition, under different stress conditions, tRNA half-molecules