The 1950s were a pivotal era in psychoanalysis. It was a time when psychoanalytic attention turned from the exploration of the internal world to the external. The influence of object relational ideas grew on various issues and Kleinian ideas gained a stronger foothold in North America. There were numerous contributions on the subject of countertransference from varying psychoanalytic schools of thought. Early preoedipal experiences between child and mother moved to the forefront of analytic theory, coupled with a growing recognition of the critical importance of this relationship on subsequent development. There was a burgeoning interest in serious personality disturbances. The first of the IJPA Key Papers Series: Papers from the Decades, this is an indispensable volume packed with classic texts that are as relevant today as they were in the 1950s, a pivotal era in psychoanalysis. They are essential reading for anyone connected to or interested in psychoanalysis.