This study quantitatively measured the operational codes of Yitzhak Rabin and Shimon Peres according to the Verbs in Context System (VICS) devised by Walker, Schafer, and Young (1998). Rabin's and Peres's basic propensities regarding the nature and conduct of foreign policy were then compared through analyses of variance, both to each other and across time. Three main trends were found in the results. First, both leaders' conception of their political environment changed over time, from basically conflictual in the 1970s to essentially neutral in the 1990s. Second, the remainder of Rabin's operational code, including a surprisingly strong predisposition to approach politics in a cooperative manner, was generally constant across time. Third, unlike Rabin, several other components of Peres's operational code underwent acute fluctuations, seemingly in response to the perceived different situational context. On the basis of these results and the operational code construct in general, a typology was created that classifies leaders according to their predisposition to pursue either cooperative or conflictual strategies and their level of responsiveness to their political environment.