The report describes the main aspects that ethics committees should consider in the evaluation of human experimentation protocols, and particularly of cancer clinical trial. Cancer clinical trials are characterized by several ethically relevant peculiarities. Among these there are, for example, the informed consent and the risk/benefit balance. The main aspects of the organization of the protocols and the protection of human subjects are described. A list of documents, guidelines and regulations that should be taken into account during the protocols’ evaluation is provided. The text is complementary to another report about the ethics of oncology clinical trial, published in the same series (Rapporti ISTISAN 09/30). This text is addressed to the members of ethics committees; the other one is addressed to researchers and clinicians who perform oncology clinical trial.