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~ establishment of a cooperative international program in strong motion measurement and data analysis; ~ organization of a coordinated international earthquake information service; ~ development of new earthquake prediction models; ~ study of the timing and methods for effective delivery of earthquake warnings; ~ assessment of technical considerations in strengthening brittle reinforced-concrete build- ings and other hazardous structures; ~ study of the international financial and insur- ance implications of catastrophic earthquakes; ~ improvement of techniques to control non- structural damage (for example, ceilings, parti- tions, windows, and other interior fixtures); ~ analysis of various strategies for preparedness and response to earthquakes; ~ study of failure modes of structures; ~ study of the special concerns in designing, constructing, and rehabilitating critical facilities; ~ improvement of guidelines for earthquake- resistant design; ~ preparation of unified risk maps that include hazard potential, frequency of occurrence, ex- pected ground motions, and site variations; ~ study of microzonation in worldwide seis- motecronic analogs; . development of seismic-safety analyses for existing dams and nuclear power facilities; and ~ continued studies of seismic gaps (faults with no recent activities) and their implications. LANDSLIDES Landslides occur in virtually every country in the world, and they have a variety of causes: heavy rains, melting snow or ice, earthquakes, vol- canoes, and human activities. Landslides often extend beyond the bounds of a single state or country, burying homes and other structures and disrupting transport and the delivery of emer- gency servIces. Notable landslides of the recent past include the Reventador, Ecuador, landslides of March 1987. A magnitude 6.9 earthquake following a month of heavy rains precipitated landslides scouring the slopes of Mount Reventador. Early estimates show 1,000 dead and 4,000 missing. In addition, the 35 event ruptured the trans-Ecuador oil pipeline - the nation's prime economic asset - causing an approximate $1.5 billion loss. In 1962 and 1970, disastrous slides plunged from the slopes of Mount Huascaran in Peru. In the 1970 event, caused by a 7.8 magnitude earthquake, nearly 20,000 died as mudflows buried the nearby towns of Yungay and Ranrahirca. In the United States, the April 1983 thaw of a heavy snow pack precipated a landslide near Thistle, Utah, which caused more than $200 million in direct losses, cutting two major highways and a transcontinen- tal rail link and damming the Spanish Fork River. Landsliding in the United States causes at least $1-2 billion in economic losses and 25-50 deaths each year. Despite a growing understanding of the geology of landslides and a rapidly developing engineering capabiliry for landslide control, losses continue to increase. This rise is largely a con- sequence of residential and commercial develop- ment that continues to expand onto the steeply sloping or unstable terrain that is most prone to landslides. There are methods for mitigating landslide losses. Land use management, building and grad- ing codes, the use of well-designed engineering techniques for landslide control and stabilization, the timely issuance of emergency warnings, and the availability of landslide insurance can signifi- cantly reduce the catastrophic effects of land- slides. Though some techniques for predicting landslides have been developed, research in this area is insufficient. For example, recurrence inter- val techniques and other temporal descriptions of risk are essentially unexplored. Some research has been carried out on the use of early warning systems to alert the public to individual local landslides, and there have been a few successful demonstrations. But there has never been exten- sive implementation of an early warning system in any country. Successful and cost-effective landslide mitiga- tion programs can be implemented, and such programs do exist Uapan, for example). Though there have been some impressive local demonstra- tions of landslide control in other countries, information about them has not been widely disseminated. Nonetheless, much can be done to reduce landslide losses everywhere. There are obvious needs for geologic and engineering research,