Globally, aquaculture has faced severe economic challenges with various infectious diseases, particularly those of bacterial origins. Even though multiple preventative and therapeutic approaches are being employed simultaneously to identify and treat these diseases, vaccinations with broad-spectrum activity remain an essential preventive tool in aquaculture. However, treatments such as probiotics and antibiotics appear to be less successful when disease-causing microorganisms become resistant to routinely used medications and foods containing antibiotics and when new mutant strains emerge. Therefore, vaccine development is considered an efficient method of addressing the microorganisms that cause diseases in aquatic organisms. In addition to offering some perspectives on how the area is anticipated to develop in the future, this chapter summarizes the commercially available bacterial fish vaccines.