Dear friends, colleagues, and distinguished guests,

It is my great honor to welcome you to this international conference on ADHD. Today we are celebrating the start of our journey to develop the Lancet Psychiatry Series on Attention-Deficit Hyperactivity Disorder. When completed I have no doubt that this Lancet Psychiatry Series will be recognized as a landmark in the field of ADHD and we can all be very proud to have been here to witness the first steps towards our goal. We would like to thank Joan Marsh and Dustin Graham, the editors of Lancet Psychiatry for giving us permission to develop the Series and guiding us through the process.

We have four main aims for the Series:

1. To develop a better understanding of the global epidemiology of ADHD
2. To quantify the long-term clinical, societal, economic, and political costs of ADHD
3. To identify barriers to worldwide equitable access to evidence-based ADHD care
4. To identify areas of improvement for education/training and advocacy on ADHD

For all of these we want to take a global perspective. Up until now most of the research and focus on ADHD has come from the perspective of those of us living and working in high income countries. With this Series we will be working very hard to make sure that the perspectives and needs of those living in low- and middle-income countries are properly considered.

Today the theme of our conferences is Bridging Gaps with a focus on research evidence, ADHD management, Stakeholder empowerment and advocacy. When you look through the program for today’s conference you will see the names of people from Africa, Asia, Australia, Europe, North and South America. While not everybody has been able to travel to be with us today, we are really proud to have gathered together this wonderful group of experts and leaders from lived experience, research and clinical practice around the world. By the time we meet with you at the conference we will have had our first investigators meeting and started to work on the preparation for the different work packages.

I also want to say thank you to my colleagues Professor Patrick Ip, Dr Adrienne Chan and Professor Luis Augusto Rohde who will be leading the Series with me and a particular thank you to Professor Ip and his team here at Hong Kong University for all the hard work they have put in to arrange the conference and to Hong Kong University for allowing us to use your wonderful facilities.

Another special thank you goes to The WEMP Foundation who are sponsoring the work of this Series, as well as Heep Hong Society, the Advisory Committee on Mental Health, Hong Kong SAR, Department of Paediatrics and Adolescent Medicine, and Department of Psychiatry at The University of Hong Kong, who co-organized this conference, without whom we would not be here. Thank you for the work you do to support the children of Hong Kong and the generous support you have given for our work.

Lastly thank you all for coming and supporting this conference. I am sure that you will enjoy what you are going to hear and hopefully will walk away at the end of the day with a deeper understanding not only of the impact ADHD has on people from around the world but also about some of the fantastic ways that we can help improve the lives of people with ADHD.

Professor Dave Coghill

The Chair of the Lancet Psychiatry Series on Attention-Deficit/Hyperactivity Disorder