Emergency departments (ED) worldwide have experienced dramatic increases in crowding over the past 20 years that now have reached critical levels. One consequence of ED crowding has been the routine use of ED hallways for patient care. This includes ED patients who are awaiting care but are considered unstable to remain in the waiting room, patients who are undergoing active medical and trauma treatment, and patients who have been stabilized but await transfer to an inpatient bed (boarding) or another institution. Compared with licensed hospital or standard ED beds, care in ED hallways results in increased patient morbidity and mortality, as well as patient and staff dissatisfaction. Complications experienced by hallway patients include unrecognized sudden respiratory arrest or unstable cardiac arrhythmias, delay in time-sensitive procedures and laboratory testing, delay in receiving important medications, excessive or unrelieved pain, overall increased length of stay, increased disability, and exposure to traumatic psychological events. While much has been published on the general problems of ED crowding, only recently have studies focused exclusively on the issues of providing care in ED hallways. This review summarizes the current issues, challenges, and solutions for hallway care.