Book excerpt: Written specifically for non-infectious disease specialists in both inpatient and outpatient settings, A Rational Approach to Clinical Infectious Diseases provides concise, practical guidance that mimics the decision-making process and reasoning employed by an ID physician. Using clear, understandable language, Dr. Zelalem Temesgen and his esteemed colleagues at the Mayo Clinic present the art and the context of infectious diseases together with the science, helping non-specialists apply a rational approach to the diagnosis and treatment of infectious conditions. Clearly explains the rationale of opting for one particular treatment or length of course over another in order to arrange appropriate management and follow-up. Provides focused ID decision support to questions such as: What diagnostic test should I order? What is the correct antibiotic for this patient/geographical region? Are IV or oral antibiotics most appropriate? How long should the antibiotic course be and when should it be de-escalated? What special considerations should be taken in immunocompromised patients? How often should complex infections be followed up? Uses a succinct, easy-to-read writing style, following a consistent format: Important characteristics/epidemiology; Clinical related data; Rash characteristics; Ancillary diagnostic studies; Treatment; and Other. Provides visual and quick-reference support with dozens of figures and tables throughout the text. Contains invaluable guidance to help non-specialists provide the best care for patients, stem antibiotic misuse and resistance, avoid adverse drug events, and avoid unnecessary costs.