In the present paper the prevalence of obesity (BMI greater than or equal to 30 kg/m(2)) and current physical activity levels in Irish adults have been evaluated, The prevalence of obesity in Irish adults is currently 18%. with men at 20% and women at 16%. A further 47% of men and 33% of women are overweight (BMI 25.0-29.9 kg/m(2)). Since 1990, obesity has more than doubled in men from 8% to 20%, and increased from 13% to 16% in women. The highest prevalence of obesity (30%) was found in women aged 51-64 years. Defined waist circumference action levels identified 48% of the population who are in need of weight management and who also are at a 1.5-4.5 times increased risk of having at least one cardiovascular disease risk factor. Physical activity levels were low overall. Men were more active in work and recreational pursuits than women, but women were more active in household activities. Walking was the most popular recreational pursuit. However, TV viewing occupied most of the leisure time of men and women. Higher levels of activity were associated with a lower BMI and waist circumference. The results indicate the need for sensitive and individualised strategies to promote physical activity and to achieve a healthy weight status.