This issue of Immunology and Allergy Clinics, guest edited by Mariana Castells, is devoted to Drug Hypersensitivity and Desensitizations. Articles in this issue include: Principles and Practice of Drug Desensitization; Incidence and Prevalence of Drug Hypersensitivity; Drug-Induced Anaphylaxis; Penicillin and Beta Lactam Hypersensitivity; Platins Chemotherapy Hypersensitivity: Prevalence and Management; Monoclonal Antibodies Hypersensitivity: Prevalence and Management; Injectable Drugs and MoAbs Reactions and Management with Desensitization; Delayed Cutaneous Reactions to Antibiotics, Management with Desensitization; Management of Children with Hypersensitivity to Antibiotics and MoAbs; Taxenes Hypersensitivity and Management; Progesterone Autoimmune Dermatitis; Severe Delayed Drug Reaction: Role of Genetics and Viral Infections; andAspirin and NSAIDS Hypersensitivity and Management.