Cholera is an acute intestinal infection caused by the bacterium Vibrio cholerae, which produces an enterotoxin that causes sever diarrhea which characterized by copious, painless, watery stool. Recent developments in DNA analysis techniques have introduced and have permitted studies of the epidemiology of V.cholerae on a larger global perspective. These techniques include RFLPS in different genes, plasmid profile, southern blot analysis, pulsed field gel electrophoresis (PFGE), Multilocus enzyme electrophoresis (MEE), DNA sequencing methods, and PCR. Till now, no study have been performed in Iraq concerning the genetic variation in clinical and environmental isolates of V. cholerae isolated during the past outbreaks periods that occurred in different parts of Iraq from 2007 to 2009. This book provides several methods, including traditional and genetic methods for detection of susceptibility, virulence factors, and molecular epidemiology of Vibrio cholerae isolated from patients and environment in Iraq.