The term “Marjolin's ulcer” is often used to describe the formation of neoplastic changes in the scar tissue of chronic ulcers. This type of carcinoma is most often seen in postburn scars, but it may be seen in many types of chronic wound scars. The most common cell type is squamous cell carcinoma. Squamous cell carcinomas resulting from Marjolin's ulcers have a much greater tendency to metastasize than squamous cell carcinomas arising from other causes, which makes early diagnosis imperative. The 2 case studies in this article describe Marjolin's ulcers occurring in chronic pressure ulcers, which should alert the clinician to the possibility of malignancy in any long-standing wound with an atypical presentation.