The chapter provides a comprehensive overview of the biodiversity and significance of Vibrio species. It begins with the historical discovery of *Vibrio cholerae* by Filippo Pacini in 1854, followed by the work of John Snow and Robert Koch in understanding the epidemiology and pathogenicity of cholera. The text then discusses the ecological distribution and importance of Vibrio species in aquatic environments, highlighting their role in nutrient cycling and symbiotic relationships with marine organisms. It also covers the human pathogens, such as *V. cholerae*, *V. parahaemolyticus*, and *V. vulnificus*, and their impact on public health, particularly in developing countries. The chapter further explores the pathogenic effects of Vibrio species on coral reefs and aquaculture, emphasizing the need for environmentally sustainable practices. Finally, it details the methods for isolating, maintaining, and genotypically identifying Vibrio species, including techniques like amplified fragment length polymorphism (AFLP), fluorescence in situ hybridization (FISH), and microarrays.The chapter provides a comprehensive overview of the biodiversity and significance of Vibrio species. It begins with the historical discovery of *Vibrio cholerae* by Filippo Pacini in 1854, followed by the work of John Snow and Robert Koch in understanding the epidemiology and pathogenicity of cholera. The text then discusses the ecological distribution and importance of Vibrio species in aquatic environments, highlighting their role in nutrient cycling and symbiotic relationships with marine organisms. It also covers the human pathogens, such as *V. cholerae*, *V. parahaemolyticus*, and *V. vulnificus*, and their impact on public health, particularly in developing countries. The chapter further explores the pathogenic effects of Vibrio species on coral reefs and aquaculture, emphasizing the need for environmentally sustainable practices. Finally, it details the methods for isolating, maintaining, and genotypically identifying Vibrio species, including techniques like amplified fragment length polymorphism (AFLP), fluorescence in situ hybridization (FISH), and microarrays.