The 27th Winter School `Geometry and Physics' took place at the usual place, the village Srni in the Czech Republic, in the period January 13 - January 20, 2007. The Winter School was organized by the Union of Czech Mathematicians and Physicists, together with the Charles University and the Masaryk University, with financial support by the International Erwin Schr\"odinger Institute for Mathematical Physics.

During the School, 6 invited lecture series were presented: *Twisted
cohomology and Dirac geometry* by **Anton Alekseev**, *Jet
isomorphism for conformal geometry* by **Robin Graham**, *An
introduction to vertex algebras* by **Victor Kac**, *Double affine
Hecke algebras* by **Siddhartha Sahi**, *Algebroids and sigma
models* by **Thomas Strobl** and *Small unitary representations*
by **David Vogan**. In the rest of the program, many further lectures,
communications, and posters were presented in two sections.

The Proceedings of this School contain 12 contributions by the participants.

Martin Cadek

editor