Informed consent means approval of the legal representative of the child and/or of the competent child for medical interventions following appropriate information. National legal regulations differ in regard to the question when a child has the full right to give his or her autonomous consent. Informed assent means a child's agreement to medical procedures in circumstances where he or she is not legally authorised or lacks sufficient understanding for giving consent competently. Doctors should carefully listen to the opinion and wishes of children who are not able to give full consent and should strive to obtain their assent. Doctors have the responsibility to determine the ability and competence of the child for giving his or her consent or assent. All children, even those not judged as competent, have a right to receive information given in a way that they can understand and give their assent or dissent. This consent/assent process must promote and protect the dignity, privacy and confidentiality of the child and his or her family. Consent or assent is required for all aspects of medical care, for preventive, diagnostic or therapeutic measures and research. Children may effectively refuse treatment or procedures which are not necessary to save their lives or prevent serious harm. Where treatment is necessary to save a life or prevent serious harm, the doctor has the duty to act in the best interest of the child. However, parents may also refuse to consent and in this case national laws and legal mechanisms for resolving disputes may be used.