Contents: Demographic transition: definition, evidence, explanatory models; A quantitative evaluation of the impact of population laws on fertility; A conceptual model of health; Health planning; A cost-benefit study of iodine supplementation programmes for the prevention of endemic goitre and cretinism; The influence of nutrition and medical innovations on health conditions in the USA, 1930--1975; Measured influence of nutrition on socio-economic development; Nutrition and fertility: some iconoclastic results; Index.