Vanillin is the world's most popular flavour compound. It is the key constituent of the natural vanilla flavour obtained from cured vanilla pods. The isolation of vanillin from vanilla pods is a laborious and costly process. Currently, less than 1% of the globally produced vanillin is derived from vanilla pods, while the greater part is produced synthetically. Industrial application of bioengineered microorganisms for vanillin production has gained quite a lot of attention not only from the flavour and fragrance industries, but also from environmental groups, the general public and politicians. The recent identification of VpVAN from the vanilla orchid can contribute to an entirely new opportunity for biotechnology-based production of natural vanillin. In the following sections, we give a thorough introduction to vanilla plants, pods and vanillin biosynthesis in the vanilla pods and highlight the current state of biotechnology-derived vanillin synthesis using bacteria, fungi and yeast as microbial production hosts.