Dr Jeffrey R. Botkin,1 in his article "Informed Consent for Lumbar Puncture," which appears in this issue of AJDC, provides physicians with an adequate legal definition of the concept of "informed consent." While I might, on technical grounds, have some objections to the way he describes the exceptions to the requirement for informed consent (see below), I think his articulation of the general principles is useful. Unfortunately, informed consent is not a concept with unvarying meaning. It is used in many See also p 899. different contexts and has many different meanings, depending on the court or commentator who is attempting to use the phrase. The two words, however, have generally accepted contextual meaning. Thus, "informed" means knowing, understanding, or aware. It does not mean the mere telling of fact, particularly when that information is not understood by the recipient. Thus, if I give the information in a language