The converse of these arrangements whereby an administrator is compelled to take prescribed action upon the request, or upon a finding of others, is the situation in which he may be barred from taking contemplated action, in consequence of a request or finding coming from another agency. Our final illustration falls into this bracket. The President was permitted by the Export Control Act of 1949 to “prohibit or curtail the exportation from the United States ... of any articles, materials, or supplies, including technical data.” But he could not exercise this power “with respect to any agricultural commodity, including fats and oils, during any period for which the supply of such commodity is determined by the Secretary of Agriculture to be in excess of the requirements of the domestic economy.”[691] INTEGRATIVE RELATIONSHIPS The statutory provisions enumerated above have the apparent objective of facilitating communication between agencies or introducing checks and balances--contrived frustrations--into the administrative process. At the least intense end of the scale is permissive interagency communication; gradually the relating of interagency communication and agency action intensifies until the point is reached at which an agency may exercise a delegated power only upon clearance with another agency, or is compelled to exercise it upon the direction of another. However, the relationship between agencies is communicative, and they do not by statute have joint responsibility for decision-making or day-to-day program development and execution. The broad group of statutes to which we now turn attempts to distribute among a number of agencies responsibility and authority for joint decision-making and action. The resources and judgment of many agencies may be focused on one program, or a system may be set up for co-ordinating the activities of many agencies toward the attainment of broad policy goals. The kind of interagency relationship contemplated by Congress appears to be more active and positive, more a harnessing of equals, than those which we have thus far reviewed.[692] Four principal categories of statutory provisions may be distinguished under this general head. Some aim at joint decision-making by two or more agencies. Others enjoin agencies to “co-operate” in the administration of a given program. A third group establishes mutual assistance arrangements among agencies. Finally, we have those statutory provisions which seek co-ordination of interagency activities.[693] JOINT DECISION-MAKING