This chapter describes the approach to child psychoanalysis and psychotherapy of Melanie Klein and the British school of object relationships. Melanie Klein introduced highly innovative ideas on the use of play as a way to understand the emotional world of young children. She also understood a number of “primitive defense mechanisms” that can be readily seen in children and adults, such as “manic defenses’ and “projective identification”. She saw the paranoid/schizoid approach to people that is seen in many adults and some children, particularly when they have been neglected or abused. Klein saw as a developmental accomplishment to arrive at the”depressive position”in which a person can see the positive and the negative in others (and themselves) and integrate them without choosing one side or the other. She embraced the notion of the death instinct as opposed to the libido, which most psychoanalysts did not adopt. Klein’s contributions should be of great interest to those who work with children and adolescents in very adverse circumstances.