Exudates from the vagina and uterine cervix of ten patients suffering from genital candidiasis (Candida albicans) were studied with transmission and scanning electron microscopy and with histochemical techniques in order to find the precise location of the Candida infection and to examine the relationship between the vaginal and cervical cells and the infecting yeasts. It was found that Candida species can penetrate, invade, develop and proliferate within the deep layers of intact cells of the cervix and vaginal mucosal epithelium. The presence of mucopolysaccharides in the glycoproteinaceous coat of blastospores and pseudohyphae was demonstrated both outside and within squamous epithelial cells. The importance of the integrity of the glycoprotein coat during the pathogenesis of human infection with C. albicans is therefore emphasized. Furthermore, the histoinvasive yeast apparently produced cytolytic enzymes during its growth within the human vaginal and cervical mucosal epithelium. The intracellular growth of Candida organisms may represent a protective mechanism of the fungus against the host and a manner of resistance to antimycotic therapy.