According to international and national agreements and conventions children have a right to express their views in all matters affecting them. However it is one thing to state that children have a right to express their views and another to stipulate to what extent they have a right to participate in decision-making about their medical treatment, participation in medical research or in clinical trials. At the conference Children’s Participation and Decision-making in Medical Matters, organized 2012 by the Nordic Committee on Bioethics, various participants discussed how this right should be interpreted and applied in different contexts and situations. This conference summary highlights the main themes of the conference.