The article discusses the problem of the succession to the throne in late Byzantium. The “idea of the imperial dynasty” finally took shape under the Palaiologoi, as the emperor's proclamation of his co-ruler and successor became a way of strengthening the principle of dynastic power transfer. The research focuses on the institution of co-rulership and its role for the strengthening of the principles of dynastic succession to the throne in the period of civil conflicts in the fourteenth century. The author of this pa­per argues that there were several scenarios of the succession to the throne which did not contradict to the “dynastic feelings” of the imperial family and Byzantine society. The analysis undertaken suggested that the Palaiol-ogoi set great store by the institution of co-rulership, considering that this was the way to secure dynastic power transfer. The title of co-emperor was important instrument of power during the periods of civil war: the desig­nation of a co- emperor could consolidate the dynasty's power and appease the conflicting parties, while the loss of this status led to the aggravation of the conflict. All the parties of dynastic struggles understood co-rulership as the only legitimate way to the succession to the throne.