An investigation of postural sway and bodyweight distribution in standing was carried out using the Nottingham Balance Platform (NBP). The aims were to provide normative data for subsequent studies on stroke patients and to show the effect of age and sex on these variables. Male and female volunteers were recruited from hospital workers, hospital visitors and members of a local community centre. Each subject was assessed using the N BP, a limb load monitor based on load cells and a microcomputer. Weight distribution was expressed as the balance coefficient, which is the mean proportion of body weight on the left leg calculated over 30 seconds. Postural sway was calculated from the deviation from that mean and expressed as the sway coefficient. The 403 volunteers included 269 women and 134 men, age range 18-87 years (mean 50). There was a significant difference between the sexes for both postural sway (p < 0.05) and weight distribution (p < 0.01) and significant correlations between age and postural sway (p < 0.001) and age and weight distribution (p < 0.001). The results provided baseline data allowing for age and sex differences for further studies with stroke patients.