On behalf of the organising committee, it is my pleasure to invite you and your colleagues to attend the WACBE World Congress on Bioengineering 2009, which will be held in Hong Kong, 26th to 29th July 2009. The World Association for Chinese Biomedical Engineers (WACBE) organises biannual World Congresses. The first congress was held at Taipei in December 2002; the second was held at Beijing in September 2004; and the third was held at Bangkok in July 2007. All the three congresses brought together many biomedical engineers from over the world to share their experiences and to exchange views on the future development of biomedical engineering. The 4th WACBE World Congress on Bioengineering 2009 in Hong Kong will continue to offer such a networking forum for bioengineers to keep abreast of the latest development of the field. The Congress will cover all related areas in bioengineering and special symposiums will be arranged in the hot themes. Apart from the scientific programmes including invited plenary and keynote speeches, special symposia, free paper presentations, and product exhibition, student activities and social programmes are also available. We will strongly encourage students and young academic staff to join this Congress. Special activities for students and young researchers to meet those internationally renowned scientists will be organised. Awards for the best papers for innovation will be set up to young investigators. The WACBE World Congress on Bioengineering 2009 will be a memorable event for colleagues and friends from all over the world to establish friendship, to promote academic exchanges at an international level and to stimulate the interests of biomedical engineers. I look forward to welcoming you to Hong Kong.