The Scottish Heart Health and Scottish MONICA studies included measurements of serum total cholesterol in 10 450 representative men and women aged 25-64 years recruited across Scotland in 1984-86. The results were typical of Britain as a whole. A new graph, called the HOTH graph ("how often that high?"), shows the percentage of the population with serum total cholesterol at or above any given value. Median (equal to mean) cholesterol levels in men were 5·5, 6·0, 6·3, and 6·2 mmol/1 in successive 10-year age groups 25-64, whilst equivalent values in women were 5·2, 5·5, 6·4, and 7·2 mmol/l. By comparison with other countries these are high, but the percentage of the population above specific cut-points is disproportionate, varying considerably by age and sex. Application of imported cholesterol management algorithms, based on global cut-points, would lead to an overwhelming caseload of patients needing intensive lipid investigation and management, dominated by older women, and incurring great costs. 35 % of the population 25-64 years old would be at or above 6·5 mmol/l and 11% at or above 7·8 mmol/l. A population diet and multiple-risk-factor strategy would be more feasible and rational than a one-dimensional cholesterol cut-point approach.