INTERMAP has already collected standardized comprehensive dietary and blood pressure data on all individuals in its 17 samples (four 24-hour dietary recalls/person yielding data on 60+ nutrients, including 19 amino acids, two 24-hour urine specimens/person with data on Na, K, urea N, creatinine, volume; eight standardized systolic blood pressure/diastolic blood pressure measurements/person; other data). Urinary concentrations of amino acids were analyzed chromatographically by high performance automatic amino acid analyzers in the INTEPMAP Central Laboratory in Leuven, Belgium. Regression coefficients for amino acid-blood pressure relationships were computed without and with correction for reliability (regression-dilution bias); sample-by-sample with pooling by country, region, and then overall; also by gender; for persons not on antihypertensive treatment; nonhypertensives; those free of a history of recent diet change; by education; to evaluate comprehensively whether urinary amino acid excretion could add meaningfully to dietary data to give a better total understanding of relationships of dietary protein-amino acids to blood pressure.