The year 2007 is the tercentenary year of the birth of Leonhard Euler, an event that is celebrated by many scientific and cultural activities. It is, moreover, the 250th anniversary of the publication of his Principes Généraux du Mouvement des Fluides (General Principles of the Motion of Fluids). This article first introduced the celebrated Euler equations of fluid motion and arguably started modern hydrodynamics, which is still a very vigorous area of research with many applications and many open problems.

On this occasion a major international and interdisciplinary conference took place in the Alpine resort of Aussois (reachable by train from Geneva, Milano, or Paris in a few hours) from 18 to 23 June, 2007. The conference brought together about 95 invited senior researchers and 45 selected young scientists.

In faithfulness to Euler's legacy, which embraces theory as well as applications, the conference covers a broad range of disciplines and approaches. There were 7 Survey Lectures, 26 Invited Lectures, 2 Poster Sessions and 7 Discussion Sessions. No parallel sessions were planned.

The issues within the scope of the conference include in particular the following:

• the origin of the Euler equations in the context of 18th century research;
• the ability of non-smooth solutions to the Euler equations to describe dissipative and turbulent behaviour, as foreseen by Onsager;
• the presence or not of finite-time blow-up of initially smooth solutions in three dimensions;
• very high Reynolds number turbulence;
• cold dark matter in cosmology as an ideal fluid and the problem of multi-streaming;
• the fluid dynamics of the atmosphere, oceans, and planets, and issues of climate dynamics;
• the Euler equations, aerodynamics and the design of aircrafts and automobiles.

The Scientific Committee		Survey Lecturers
C. Bardos (Paris) R. Benzi (Rome) J. Bertrand (Toulouse) Ph. Blanchard (Bielefeld) E. Bodenschatz (Goettingen) G. Eyink (Baltimore) U. Frisch (Nice) – chair T. Kambe (Tokyo)	K. Khanin (Toronto) E. Knobloch (Berlin) G. Lebeau (Nice) H. K. Moffatt (Cambridge, UK) R. Moreau (Grenoble) R. Morf (Villigen) A. Sobolevskii (Moscow) E. Titi (Rehovot/Irvine)	F. Busse (Bayreuth) O. Darrigol (Paris/Berkeley) and U. Frisch (Nice) G. Eyink (Johns Hopkins) M. Ghil (Paris/Los Angeles) J. Gibbon (Imperial College) P. Perrier (Dassault Aviation, Paris) I. Procaccia (Weizmann Institute)

A special issue of Physica D will be devoted to articles emanating from contributions to the Conference. It will also include an English translation of Euler's key papers on the subject.

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