The 13th edition of Ananthanarayan and Paniker’s Textbook of Microbiology, has been meticulously developed to align with the principles of the competency-based medical education (CBME) curriculum prescribed by the National Medical Council (NMC). The content in this edition has been curated not only to cover the essential aspects of microbiology but also to foster the development of core competencies that are vital for medical practice. The approach integrates foundational knowledge with clinical applications, encouraging learners to bridge the gap between theoretical understanding and practical patient care. The introduction to bacteriology has been split into two chapters—Basic Concepts of Bacteriology, which deals with concepts such as staining, growth characteristics, and identification methods, and Systematic Bacteriology, which has been expanded to include the virulence factors and diseases caused by various organism groups.