The article presents information on the identifying behaviors of the social work client which are signs of his will and ability to work productively on his problem and are the dynamics social workers seek to influence in order to effect movement and change. In their diagnostic thinking social workers have sought to ascertain the treatment potentials within the client himself, the agency and the social environment in order to anticipate outcome, in part, but chiefly in order to utilize those potentials of treatment ability in the surest and most economical ways. However, the focus is more upon the nature of the problem — the physical, psychological, or social sickness — than upon that to which it was joined. Social workers have been more knowledgeable about the dynamics of pathology in a person or in his situation than about the dynamics of the whole person and situation of which the sickness was only one part. To be sure, in their diagnostic work social workers have set down orderly accounting of "assets" alongside "liabilities" or "ego strengths" alongside "ego weaknesses."