After 20 years of stewardship of the Archive for Rational Mechanics and Analysis, John Ball and Dick James have decided to step down as Editors-in-Chief. This is an occasion to thank them not only for their everyday dedication to the journal but also for their inspiring leadership of the research community associated with it.

The term Rational Mechanics originated in discussions concerning the deepest foundations of mechanics. Mathematical topics and their communities evolve, and the journals serving them must reflect this evolution to remain relevant. It is the leadership of John and Dick that has helped the Archive to maintain its impact while preserving its unique identity. Bringing together perspectives of an analyst and a mechanician carrying out experiments, the scientific work of John and Dick opened new directions of research that have been very natural for the Archive and have attracted many talented researchers to its community. Some of the recent innovative developments in non-linear partial differential equations can be traced back to questions in mechanics originally asked by John and Dick, and to their perceptive comments. The ability of John and Dick to convince a number of exceptional mathematicians to join the editorial board of the Archive has been a decisive factor in the journal’s success.

The original goal of the Archive persists: to attract important developments in continuum mechanics and non-linear partial differential equations. This is to be understood in a broad sense, and may include statistical and quantum mechanics, general relativity and other classical field theories, dynamical systems, and geometric as well as probabilistic concepts. Sometimes the most exciting developments cannot be foreseen and thus are difficult to label. To detect those developments, the Archive relies on its board members, which have an unusually free hand in making their decisions.

The challenges for today’s mathematical journals are well-known: an ever-growing number of papers is being written, but only a minority of them are actually read. It is increasingly difficult to get in-depth referee reports. We wish to attract thoughtful papers that will be read, not just browsed.

To edit the Archive is both a great honor and a great responsibility. The remarkable history of the journal, its achievements in helping to create a vibrant research community, and its important role in serving the community’s needs will be constantly on our minds. We look forward to working with the editorial board to continue the successful journey of the journal.