The EU has been provided with a regulation that promotes and regulates paediatric medicines. The initiation of the preparation of this regulation was made in response to the widespread demand of the scientific community, the health authorities and even of public opinion. The reasons why medicinal products need to be studied in children are clear: more than 50% of the medicines used to treat the children of Europe have not been tested; the paediatric population is a vulnerable group with developmental, physiological and psychological differences from adults; there are differences in pharmacokinetics and dynamics; growth and maturation processes affect them. Also, there is a general lack of information and appropriate pharmaceutical formulations. To overcome this lack, clinical trials have to be carried out on children, which, in turn, create serious scientific, legal and ethical problems. Specific protection should be defined for research performed on children at all stages and ages. In order to address the concerns about trials in children, the EU directive on clinical trials lays down specific requirements to protect children who take part in clinical trials in the EU. The commission is developing guidelines to implement this directive. Once more, the European Medicines Agency (EMEA), in its function as the scientific organ of assessment and evaluation of medicinal products, prepared the scientific and technical foundations for the proposed legislation.