Historians commonly criticize studies in a more behavioral mode as bei
ng ''ahistorical''; that is, they lump together a disparate group of e
vents without regard for their historical contexts. We propose to focu
s on what may be the most obvious and serious form of historical conti
nuity: repeated conflict among the same set of states, or what we refe
r to (in accordance with the small but growing literature) as ''enduri
ng rivalries.'' Specifically, we (1) explore the theoretical relevance
of the concept of enduring rivalries, (2) define the concept of endur
ing rivalries, (3) evaluate current operational criteria for enduring
rivalries, and (4) describe empirically the rivalries generated by tho
se criteria.