The paper deals with the question about the degree to which the perioikoi were integrated into the structure of the Spartan army. The author draws attention to a number of inconsistencies and contradictions of sources containing some information on the Lacedaemonian army's tactical organization at its different stages. The author mainly focuses on the textual analysis of the passage of De Republica Lacaedemoniorum in which Xenophon speaks about regular tactical units of Spartan troops (Rep. Lac. XI.4). The author overturns the arguments for the hypothesis that the integration of periokoi and spartiatai in the form of common fighting units took place only after the defeat in the battle of Leuctra in 371 BC.