The Nordic Monitoring System is a study of diet, alcohol, physical activity, overweight and use of tobacco and nicotine products among adults aged 18-65 and children aged 7-12 in Denmark, Finland, Iceland, Norway and Sweden. This report describes the third data collection in the Nordic Monitoring System conducted in 2024 and presents the status and development from 2014 to 2024. Behaviours in terms of diet, physical activity, alcohol use and nicotine products in the Nordic countries have become less healthy and sustainable, and the prevalence of obesity has increased. Therefore, policy factors such as pricing and taxation can play a crucial role in promoting healthier and more sustainable behavioural changes across the Nordic region.