During the past 7 years, I have been privileged to be the Editor-in-Chief of this journal. My role formally commenced with issue 1934, which was published on 13 January 2011; since then 176 issues of the journal have been published, each focused on a particular scientific theme. Our scientific territory is the physical sciences, namely astronomy, chemistry, computer science, Earth science, engineering, mathematics and physics. Our aim has been to ensure that each issue—comprising a mixture of reviews, research articles and discussions/opinions set in context by an introduction/preface—represents a landmark in its field.

Since 2011, notable theme issues published have included:

• — The sustainable planet: opportunities and challenges for science, technology and society [1].

• — Physics at the high-energy frontier: the Large Hadron Collider project [2].

• — Surface science in the interstellar medium [3].

• — Density functional theory across chemistry, physics and biology [4].

• — Unifying physics and technology in the light of Maxwell's equations [5].

• — Cometary science after Rosetta [6].

As several of these titles clearly illustrate, many significant scientific advances involve expertise from two (or more) disciplines.

Important sources of the journal's theme issues are the prestigious Royal Society Discussion and Theo Murphy meetings. These theme issues are augmented by a refereed selection from a considerable number of submissions provided by scientists who are interested in being a Guest Editor of an issue dedicated to a scientific topic of their choice.

The most notable event during my tenure as this journal's Editor-in-Chief was the celebration of the journal's 350th anniversary in 2015. As part of these celebrations a special issue ofPhilosophical Transactions of the Royal Society A was published in April 2015. This special issue featured 16 of the major contributions to advances in scientific knowledge and understanding that had been published in the journal during its lifetime [7].

Philosophical Transactions originated due to the vision and commitment of Henry Oldenburg, who was the Secretary to the Royal Society from 1663 to 1677. From its inception the journal played a major role in establishing two vital principles of scientific publishing: the establishment of priority for a scientific innovation and the peer reviewing of submissions. Despite all of the major changes that have taken place in scientific publishing since 1665, especially during the last (say) 50 years, these two principles are still fundamental objectives of all leading scientific journals.

I have enjoyed working with a team of dedicated professionals to produce new issues ofPhilosophical Transactions A. The considerable range, variety and scientific significance of the topics that the journal is requested to consider for publication have ensured my continued interest in, and commitment to, my editorial responsibilities. However, I have been frequently challenged; thus, the majority of the submissions received have involved a topic outside my professional comfort zone. In this latter respect, and many others, the scientific knowledge of, and advice provided by, members of the journal's Editorial Board has been indispensable. Collectively, these board members possess expertise and experience that cover the journal's scientific remit. Around half of the members of the Editorial Board are based in the UK, with the remainder being located in a wide range of other countries. The spread of scientific expertise and geographical location serves to enhance the journal's profile and provides access to a valuable management information base. I thank all of the board members who have served during my time as Editor-in-Chief for their many constructive contributions to the journal's activities.

I am pleased to record my appreciation of the professionalism and efficiency of all of the Royal Society publishing staff with whom I have interacted during these past 7 years. The journal's Commissioning Editor has the major responsibility for the day-to-day operations of the journal. This includes monitoring a wide variety of aspects of the journal's performance, notably its reception by the scientific community, as well as initiating discussions of possible strategic developments. When I became Editor-in-Chief Suzanne Abbott was the journal's Commissioning Editor; Suzanne left this post in 2013 and Helen Eaton (Senior Commissioning Editor ofPhilosophical Transactions B) looked after both journals until Bailey Fallon was appointed in September 2013. I have derived considerable benefits from my productive interactions with all of these individuals and I thank each of them for the considerable assistance and perceptive guidance they have provided. Also, I thank Dr Stuart Taylor (Publishing Director) and Phil Hurst (Publisher) for the considerable support and encouragement that I have received from each of them. Once a theme issue is finalized, the production of the publication is led by the Production Editor, currently Thadcha Retneswaran. I thank her and the other members of the editorial and production teams past and present for the consistently high quality of the final productand their constructive interactions with so many of the journal's guest editors. Also, I thank Debbie Vaughan and Felicity Davie of the Royal Society's marketing team for raising the profile and enhancing a general awareness of this and the Royal Society's other journals.

I send my good wishes to the new Editor-in-Chief of the journal, Professor John Dainton (Sir James Chadwick Professor of Physics (Emeritus), University of Liverpool). I am confident thatPhilosophical Transactions of the Royal Society A will continue to publish authoritative and accessible accounts of important scientific advances, developments in prospect and challenges to be addressed, thereby maintaining the journal's prominent position in the world's scientific literature.