About four of every 100,000 Emergency Department (ED) visits result in an allegation of malpractice. This analysis of 1,300 medical malpractice cases involving emergency care, provides insight into what is driving these claims. Because their care is episodic and fragmented, ED patients present multiple care and management challenges, especially in the diagnostic process. This Report offers a look at what goes wrong and why in a busy Emergency Department providing valuable information for organizations working to mitigate these risks.