The National Study of Health and Growth (NSHG) was set up in 1972 to monitor growth in primary schoolchildren. Each year 8000 children in England (most parts except the south-east) and 2500 in Scotland are measured. Data from the first year have been used to obtain standards of height, weight and triceps skinfold for ages 5 to 11 inclusive, and ellipse contours of weight by height for each year of age. The distributions of weight and triceps skin fold were positively skew; logarithmic transformations led to satisfactory Normalized distributions. Centiles within each age group, calculated from the mean and standard deviation of the transformed variables, were closely similar to the observed centiles. Scottish children were lighter and shorter than English children in all age-sex groups. The heights and weights of English children in the NSHG were very similar to those published by Tanner, Whitehouse and Takaishi (1966). Triceps skinfold agreed closely with the data of Tanner and Whitehouse (1975) for the 50th and 97th centiles in boys, but our 3rd centile was well above its counterpart. Girls had higher skinfolds than girls in Tanner's data at the 3rd and 50th centiles. The triceps skinfolds of Scottish children were lower than those of English children throughout the age range and for all the centiles in both sexes. An example is given of the use of our ellipse contours of height and weight for surveillance of a population of children. Children's height is discussed in relation to variability over time and between different parts of the country.