ABSTRACT The sovereign Federal Democratic Republic of Ethiopia and the Republic of Kenya are two independent states geographically located in the Horn of Africa; they share a common border, similar challenges and arguably common opportunities. The two states have had diplomatic relations for close to six decades. This study was guided by three objectives; to examine the factors that determine foreign and policy interests of the two countries, to analyse responses of Kenya and Ethiopia to the changing global environment, to examine the similarities and differences of the foreign policy and diplomatic styles of the two countries. From the study it emerged that if security and conflict challenges from the region are factored in foreign policy of the two states towards each other, then they will be responsive. It also emerged that If the foreign and policy responses of Kenya and Ethiopia are not responsive to the global environment, then change will be of no essence. Moreover the research findings noted that foreign and diplomatic policies of Kenya and Ethiopia are similar but the implementation methods are different. The study used the actor model theory, Allison’s models of foreign policy decision making are based on three levels of foreign policy analysis. Allison argues that, these models are useful in decision making by states. Allison argues that, in foreign policy, states decisions are made by considering three main models namely, rational actor approach, organizational process and bureaucratic politics model. The rational actor approach contends that, governments are unified and rational entities, seeking to achieve well defined foreign policy goals in the international system. The Rational Actor approach presumes that, individual actors have complete freedom of action to achieve goals that they have articulated through a careful process of rational analysis involving full and objective study of all pertinent information and alternatives. At the same time, it presumes that this central actor is so fully in control of the apparatus of government that a decision once made is as good as implemented. The rational actor model ignores the fact that the individual, say the president is surrounded by a bureaucratic from which he has to obtain information and discuss policy alternatives. Such a structure may influence decisions since it the same structure which is providing the information and alternative from which the rational leader is to make his choice from.