Infectious skin diseases pose considerable treatment challenges, especially given the recent appearance of several highly virulent pathogens as well as the rising number of immunocompromised patients in the United States. This article discusses common bacterial, fungal, and viral skin infections with an emphasis on cellulitis, dermatophyte infections, and herpes simplex viral infections. Disease pathogenesis, treatment, and cost of treatment are addressed with an emphasis on therapeutic needs and future research directions. Common priorities for all infectious skin disease categories include increased disease surveillance, study of existing treatments, and efforts in drug development.