A Workshop on maternal nutrition, supplementation programmes, and infant health was held in Panajachel, Guatemala, in March 1979. Scientists, public health specialists, and national planners from 12 countries of four continents participated.Results from eight recently completed maternal nutrition intervention studies were reviewed. These studies show that, in malnourished populations, nutritional supplementation during pregnancy increases birth weight. According to the results, the effects were most marked when supplementation was provided in the third trimester of pregnancy, but benefits from supplementation initiated earlier in gestation were also reported. Such changes may be important in terms of resultant decreases in the proportion of low birth-weight infants, reductions in perinatal and infant mortality, and its effects on subsequent child development. Data from several of the studies support the importance of maternal nutritional supplementation on perinatal and infant mortality. Whether the beneficial effects are due to added proteins or energy is a subject not conclusively resolved in these studies, although energy would appear to be a very important factor in the situation of the populations studied.Present evidence indicates that a large proportion of women of reproductive age are malnourished; many of them also have nursing babies or young children. It was the consensus that sufficient data now exist to anticipate a beneficial impact of maternal nutritional supplementation programmes on maternal and infant well-being. Further knowledge will facilitate refining of capability to intervene, but lack of full knowledge concerning the relationship between maternal malnutrition and infant health should not be used as an excuse for not intervening or not developing appropriate programmes.In approaching the problem of maternal malnutrition, governments should avoid two extremes: (1) generating national policies and programmes based on population averages which do not permit identification of those population segments which are most in need of nutrition and health services; or (2) deciding to postpone the establishment of policy and implementation of programmes until after extensive and detailed national surveys have been completed. Usually, needy populations can be identified with the existing information coupled with simple and easily conducted community surveys in areas projected to have the greatest number of malnourished women and infants. Such community surveys will aid in designing the most appropriate intervention.The establishment of policy and development of strategies will require decision and commitment at the highest executive level possible within the government. In accordance with this commitment, an integrated approach to improve the nutritional status of pregnant women, lactating mothers, and young children can then be developed utilizing resources from diverse sectors: agriculture, health, social welfare, education, and national planning, as well as from private organizations.Development and implementation of maternal nutrition improvement programmes-whether supplements, better use of local foods, fortification of foods, development of appropriate technology, or extension of preventive health care-must from the outset involve communities and representatives of the beneficiaries. Unless recognition of the problems and their solution within families and communities is achieved, long-term success is unlikely. Community resources must be marshalled or trained to provide and extend services. Community attitudes and practices, vis-à-vis the needs of mothers and infants, must also be changed. In particular, traditional medical care oriented to curing illness must be reoriented towards the prevention of illness by drawing upon local human and other resources.The long-term goal must be the attainment of selfsufficiency on the part of the populations being served, with emphasis on production and use of locally available and acceptable foods. All programmes, whether they concentrate on educational or supplementary activities, should therefore keep this goal in mind from the very outset. This is especially true in the case of nutritional supplementation programmes since, although they may be expected to provide demonstrable benefits when used to meet identified deficiencies in malnourished groups, they may lead to dependence and prevent the development of self-sufficiency.No matter what type of nutritional improvement programme is implemented, it must have a built-in monitoring and evaluation system to improve services and expand coverage, as needed.The improvement of the nutritional status and wellbeing of women and children is the responsibility of national governments. Nevertheless, international and other agencies can contribute to this effort by encouraging governments to recognize the problem, by directing programmes to these target groups, by providing training and consultative services, and by supporting operational research leading to appropriate technology.From the data reviewed in this report, it is clear that maternal nutrition is intimately intertwined with infant health and survival. Thus, the problem of maternal malnutrition during pregnancy and lactation presents a potentially and very serious obstacle to social development. © 1982 Oxford University Press.