In his ‘Introduction to the Report of the Secretary-General on the Work of the Organization’, Dr Kurt Waldheim stated in August 1976 that ‘… in these last years I have learnt to appreciate the extraordinary range, variety and sometimes the unexpectedness, of the Organization's activities, the great possibilities as well as the obstacles which it confronts, and the wealth of human talent and dedication which is to be found among the national representatives and international civil servants who work in the United Nations System’. Martin Hill was one of these dedicated international civil servants, with an experience in addition which was unrivalled in international administration. He has brought to this study his unparalleled knowledge of the United Nations System, meticulous scholarship and much painstaking attention to the details of the relationship between various organizations.

The present work is an expanded version of an earlier study which was published by the United Nations Institute for Training and Research (UNITAR) in 1974, under the title, ‘Towards Greater Order, Coherence and Coordination in the United Nations System’. That study exerted a significant influence on discussions and decisions on development and coordination within the United Nations System. The importance and value of this study was recognized by the United Nations Economic and Social Council, and was thus issued as one of its documents; the Council used it extensively in the rationalization of its structures and procedures and in preparation for what was to become the historic sixth Special Session of the General Assembly.