Conscientious objection refers to the possibility that an individual decides not to comply with a legal mandate because of his or hers convictions, which is accepted by some political constitutions. The classical example is to refuse participation in obligatory military service for personal reasons of conscience, but in the present paper we refer to its use in medical practice utilizing three examples: euthanasia, abortion and the refusal to prescribe emergency contraception. We conclude that in all situations patients rights supersedes conscientious objection.