Happy Birthday Hamid Abban, Gavin Brown, Alexander Kasprzyk, Shigefumi Mori; 1. On stable cohomology of central extensions of elementary abelian groups Fedor Bogomolov, Christian Böhning, Alena Pirutka; 2. On projective 3-folds of general type with p_g = 2 Meng Chen, Yong Hu, Matteo Penegini; 3. 15-nodal quartic surfaces. Part I: quintic del Pezzo surfaces and congruences of lines in P^3 Igor V. Dolgachev; 4. Mori flips, cluster algebras and diptych varieties without unprojection Tom Ducat; 5. The mirror of the cubic surface Mark Gross, Paul Hacking, Sean Keel, Bernd Siebert; 6. Semi-orthogonal decomposition of a derived category of a 3-fold with an ordinary double point Yujiro Kawamata; 7. Duality and normalization, variations on a theme of Serre and Reid János Kollár, Hailong Dao; 8. Rationality of Q-Fano threefolds of large Fano index Yuri Prokhorov; 9. An exceptional locus in the perfect compacti cation of A_g Nicholas Shepherd-Barron, John Armstrong; 10. Variation of stable Birational types of Hypersurfaces Evgeny Shinder, Claire Voisin; 11. Triangle varieties and surface decomposition of hyper-Kähler manifolds Claire Voisin.