In July 1976, the Disaster Research Center (DRC) at Ohio State University initiated a three-year study of the organized delivery of mental health services in largescale disasters in the United States. The background of our work was the ever-increasing phenomena,' and the coming to the fore in the last decade of the provision of mental health services in American disasters.2The research was the first ever of its kind, both in its focus on the organization of service delivery and in its systematic coverage of a variety of sudden mass emergencies. Being an exploratory pioneering study, thus lacking even a descriptive base on which to build, the work aimed at obtaining generalized but empirically based observations and findings. The intent was to identify variables, to generate hypotheses, and to accumulate a conceptual framework that could serve both to order our analysis of the data, and to suggest the outlines of an eventual overall model of the phenomena.In general, the objectives were to establish the nature and the parameters of the efforts to provide mental health services in catastrophes and major stress situations. More specifically, and primarily through extensive field studies at the community and organizational levels, we sought to answer two questions: (1) What are the conditions associated with the delivery of the mental health services in disasters? That is, what are the pre-, trans-and post-disaster circumstances and factors that affect the providing of disaster-related mental health services? (2) What are the characteristics of the mental health services provided in disasters? By whom, what, for whom, where, how and when are services offered and delivered?There were three phases to the work. Phase I included developing a guiding conceptual framework. Phase I1 used the framework to obtain, through field work, answers to the two questions posed above. Phase 111 involved data analysis, an attempt to see if a theoretical model for future research could be derived, and the drawing of implications for training and planning for personnel and agencies concerned with disaster-related mental health service delivery. This paper primarily reports on the work of Phase 11, touching only slightly on what was done in Phase 111. 'For recent reviews of the literature on sociobehavioral aspects of disasters, see Barton, 1970;Dynes, 1970;Quarantelli and Dynes, 1977. *Systematic and organized efforts to provide large-scale mental health services after disasters only started in the early 1970s. notably with the Wilkes Barre Rood of 1972. Section 413 of the Federal Disaster Law of 1974 gave formal impetus to the delivery of such services by mandating that a new ofice in the Institute of Mental Health (NIMH), through the major federal disaster agency, should offer necessary help in postdisaster situations. For a discussion of the new office and its philosophy, see Frederick, 1977.