The British Medical Association, at their annual Conference held in Auckland in April, 1924, resolved that the following motion be adopted by the Council: "That this Conference can make no recommendation for surgical desexualization in the treatment of the adult sex pervert. The only safeguard for young children in this matter is the permanent segregation of the offender, either in prisons or in farm colonies. The Conference emphasizes the importance of the sterilization of the chronic mentally or morally unfit that a future generation may benefit thereby." The Committee therefore considers it necessary to set out as clearly as may be possible the result of such operations and its deductions from the evidence taken and authorities consulted as to the probability of the achievement of the result desired. To consider in the first place the operation of simple sterilization (vasectomy or salpingectomy). It is quite clear that this operation, when properly carried out, prevents procreation by the individual operated upon. Although the knowledge of the loss of this power may modify the views of life held by the individual the operation _per se_ does not affect his physical or mental health. This would be anticipated, as the production of the internal secretion of the sexual glands in either sex (ovaries or testes) continues. Sexual desire and capacity for coitus are not usually appreciably impaired by this operation, and it clearly could not be expected to restrain the sexual offender from the pursuit of his perverted modes of gratification. As, however, it appears that in a proportion of cases of sexual perversion the tendency is an hereditary one, these operations would, as in the case of the feeble-minded, tend to restrict the number of individuals in the community afflicted in this manner. The Committee would therefore recommend that simple sterilization be considered by the Eugenic Board in relation to sexual perverts. _Castration (Desexualization)._ The operation of desexualization implies the removal of the sexual glands (ovaries or testes), and involves other considerations than the operation of simple sterilization. The loss of the internal secretion of these glands may produce physical and mental changes in the individual. These effects vary greatly in degree according to the age at which the operation is performed. The earlier it is done the more decided the result. If performed _before puberty_ the secondary sexual characteristics fail to develop. The voice does not change in the male; the development of hair is more sparse; the general physical development is less masculine; and mentally the individual is less aggressive. Most pertinent of all as bearing upon the question under review, sexual desire and capacity do not develop, either at all, or at any rate, not to the same degree as in a normal individual. This result, however, is not constant, and depends principally upon the age at which the operation is performed.