Infectious diseases pharmacy practice specializes in the use of microbiology and pharmacology to develop, implement, and monitor drug regimens that incorporate the pharmacodynamics and pharmacokinetics of antimicrobials to optimize therapy for patients. The practice requires pharmacists to use clinical and evidence-driven knowledge to develop appropriate antimicrobial therapies to more rapidly resolve infections while decreasing adverse events, complications, and resistance. The practice includes direct patient care provided through interprofessional healthcare teams, collaborative leadership of antimicrobial stewardship programs, education of health care providers, preventive services including immunizations, and advocacy for appropriate antimicrobial utilization. Specialty pharmacy practice in infectious diseases uniquely improves public health by optimizing antimicrobial potential in individual patients and narrowing the resistance trends that occur in society by preventing progression of antimicrobial resistance and infectious diseases.