Fungi make an enormous contribution to our life. The role of yeast in the production of alcohol and bread is well known. We consume fungi directly in the form of edible mushrooms and in cheese, which get their characteristic flavour and aroma from the presence of fungi. Fungi are also used for the production of antibiotics and enzymes for use in the food industry. Over the last decades Fungi have been used for the production of recombinant proteins,some of which have great therapeutic potential. Although infrequently recognised as important decomposers of organic detritus, Fungi play a significant role in degrading biological matter, such as fallen leaves. In a more negative note some fungi (for example member of the genus Aspergillus and Candida) are capable of causing serious life threatening infections in immuno-compromised patients, and other fungi can be serious environmental contaminants. According to a recent publication less than 5% of fungal species are currently known, suggesting that millions of fungal species and therefore, potentially million of fungal bioactive natural products remain to be discovered.