Ecthyma gangrenosum (EG) is a cutaneous infection that most commonly occurs in immunocompromised individuals with fulminant bacteremia. EG was first described in 1897 by Canadian pathologist Dr. Lewellys Barker as a manifestation of Pseudomonas aeruginosa. Although P. aeruginosa remains the most frequent organism identified in EG, other causative pathogens have since been described. Lesions appear as gangrenous ulcers with erythematous borders. EG predominantly affects the axillary and anogenital areas, but the arms, legs, trunk, and face are also sometimes involved. Perivascular invasion and resultant ischemic necrosis of the associated skin result in the classic macroscopic appearance. Prompt recognition and empiric therapy with broad-spectrum antipseudomonal agents are of critical importance. Once microbiology results identify the causative pathogen and sensitivities are available, antimicrobial coverage should be narrowed. EG denotes a poor prognosis, particularly in immunocompromised individuals with neutropenia.