The analysis of the views of the doctrine and of the European Court of Human Rights, the Constitutional Tribunal and the Supreme Court on the concept of “the child’s welfare” allows to assume that it is the same as the “interests of the child” referred to in the preamble to The Hague Convention on the Civil Aspects of International Child Abduction. This criterion must be taken into account by the courts when assessing the grounds for refusing to order the return the abducted child under Art. 13 (b) of The Hague Convention. However it should be considered that this provision constitutes an exception to the principle of ensuring the return of the child to the state from which it was taken.