This paper is dedicated to one of most interesting representatives of the so-called Socratics - Aristippus of Cyrene, who is traditionally held for the founder of the Cyrenaic school (Cyrenaic aἵresij ). The philosophy of the the Cyrenaic School had ethics as the focal point of speculation, to be more precise - the doctrine of pleasure (hedonism). There was a well-known polemics between the Cyrenaic School and the School of Epicurus; the latter got the upper hand. Notwithstanding the success of Epicurus, the phenomenology of pleasure proposed by Aristippus deserved to be interpreted most attentively. Arguments to support the importance of the doctrine of the Cyrenaic School will be put forward. We analyze not only the Cyrenaic concept of pleasure, but also Aristippus special interpretation of full happiness.