The article focuses primarily on the growing importance of competency and insanity determinations in juvenile court delinquency proceedings. Lawyers involved in juvenile delinquency cases need to be alert to the possibility of defenses based on competency or insanity. However, lawyers requesting psychological evaluations for competency or sanity in juvenile court should also be cognizant of the need to protect the juvenile’s Fifth Amendment privilege against compelled self-incrimination. A determination that a juvenile is not competent to stand trial because of an inability to comprehend the proceedings or to assist in his or her defense or a conclusion that the juvenile was “criminally insane” at the time of the offense may abort a transfer hearing or prevent prosecutorial bindover or forestall a trial for delinquency that could result in severe and lasting consequences for the young person. Defense lawyers, prosecutors, judges and court personnel should act to ensure that an incompetent or legally insane young person is not convicted as a criminal, or even as a delinquent.