The place of mercenaries in pre-modern armies is not typically looked upon as a positive. Authors from the ancient world onward criticized the use of mercenary troops. One of the typical criticisms we hear of is that they cannot be relied upon because they have no permanent investment in the community for which they fight. In the context of the ancient Mediterranean world, we must also address the issue of mercenaries often being from a different ethnic group with considerable cultural differences between them and their allies. Despite these concerns, amongst others, mercenaries were constantly relied on in times of war. This is especially true, or so we are led to believe, of the armies of Carthage. Perhaps the earliest armies of the Tyrian colony were comprised only of citizens, but by the fourth century considerable compliments of mercenaries from around the Western Mediterranean were helping to fight their wars. The armies which fought against Syracuse and her allies under Dionysius, for example, were largely mercenary from what we hear in our sources. Famously, at the close of the First Punic War against Rome, the mercenaries in service of Carthage rebelled from the great city and fought a fairly successful war against their one time employers. In the Second Punic War, their armies, including considerable mercenary contingents, almost brought Rome to her knees. Throughout the known history of Carthage's wars, however, their mercenaries had a mixed history of courage under fire. On at least one occasion the problem was breaking ranks early to begin looting. This paper will examine the integrity in battle of mercenary units in service of Carthage and will discuss the issues of ethnicity and army cohesion.