The aim of the investigation is to throw light on the adoption institution. Much attention has been devoted to the contractual nature of the adoption which was carried out inter vivos as opposed to the unilateral nature of a testamentary adoption. In the present work it is argued that the main difference between the different types of adoption was one of procedure: adoption took place in public, in the adopter's phratry and deme, no matter whether prior to the death of the adopter or posthumously. It is also argued that it was the formal recognition of the adoptee by the adopter's phtatry and deme which constituted the adoption itself and its validity, legal as well as social. Further, the tomb cult, aspects of Athenian family-life and the Athenian legislation, which regulated it, are treated to the extent to which they have a direct influence on the Athenian institution of adoption.