Introduction

Since the spores of fungi are produced in great numbers and dispersed over considerable distances we are subject to continuous exposure to viable units of many different fungi. Not all are able to establish themselves within or on the human organism but for a number of them an inoculum of sufficient size to overwhelm the body defence mechanisms, or inoculation to a particular site, or a weakened state of the host enables them to become pathogenic. Because modification or suppression of host defence mechanisms is a common feature of many modern surgical and medical procedures these opportunistic infections are of ever increasing importance. The value of this symposium lies in the opportunity which it presents to explore many of the intriguing aspects of these opportunistic fungal pathogens.