Rumours of genetic exchange in the genus Trypanosoma were finally conf
irmed in 1986 when the first experimental evidence of sexual reproduct
ion in T. brucei was published. Since then, a number of laboratories h
ave tried to unravel the mechanism of genetic exchange in T. brucei an
d the process is also being sought in other trypanosomatids. Wendy Gib
son here gives on account of our present understanding of the process
and its significance in Nature.