The incidences of human opportunistic or secondary infections have increased dramatically due to the rise in the number of immunocompromised patients. Besides, the increasing drug resistance has also created an alarming situation, while treating the patients. This book is focused on candidiasis, an opportunistic mycosis in patients already suffering from HIV, vaginal, nosocomial infections and diabetic patients. The scientific contents included isolation of various Candida species, including albicans and non-albicans species followed by their identification and differentiation. Increasing resistance revealed by the pathological isolates towards various commercially available antifungal drugs prompted to explore and compare various novel chemical compounds, as synthesized outside with the commercially available drugs. I hope the book would be helpful to the researchers, currently working in the field of medical microbiology, especially opportunistic mycosis.