We are very pleased to invite you to participate in the 31st International Congress on Occupational Health to be held in Seoul from 31 May to 5 June 2015. The Congress is organized as the triennial congress of the International Commission on Occupational Health (ICOH). The 2015 Congress, aiming at global harmony for occupational health, will be an important milestone in meeting our challenges in protecting and promoting the health of workers at the time of rapid changes in work life and working conditions in globalizing economy. It is opportune to highlight harmonized action for managing complex risks in increasingly diverse work situations. Since the first Congress in Milan in 1906, our triennial congresses have played a leading role in advancing research and practice in occupational health and safety. The Centennial Declaration adopted at the Milan Congress in 2006 has reaffirmed our joint effort on action-oriented research and practice for health and well-being at work for all workers. The Seoul Declaration adopted by the World Summit on Safety and Health in Seoul in 2008 calls for global partnership in our field. ICOH emphasizes prioritizing occupational health on the international and national policy agendas through the development of proactive occupational community of experts to discuss innovative solution-oriented approaches. The advances in these aspects are seen in broad-ranging activities of 35 ICOH Scientific Committees that will actively take part in the organization of the symposia, mini-symposia and special sessions of the 2015 Congress. Serial sessions will be held to promote regional and networked cooperation for achieving good occupational health practices. The dialogue at the Congress will amply help us respond to varied needs of workers and advance the principles and ethics of our professional activities. We are delighted to confirm the excellent preparations for making the Congress successful and productive. The Organizing Committee headed by Mr. Hun-ki Baek, President of the Korea Occupational Safety and Health Agency (KOSHA) with renowned colleagues is assuring a top quality programme, reasonable fees and excellent facilities for realizing highly interactive exchanges of new developments. We sincerely hope that the outcomes of the Congress will help us meet our challenges through enhanced international collaboration. A very warm welcome is extended to you all. We look forward to sharing ideas based on your expertise and commitment to bridging the world.