This book brings together in a single volume the most up-to-date results in the field presented at Ultrafast Optics and Applications of High Field and Short Wavelength Sources 2005. The volume contains keynote and invited contributions together with carefully selected regular contributions. The book aims at the highest level of presentation to make it useful as a reference for those working in the field.

The 12th International Conference on Multiphoton Processes (ICOMP12) and the 3rd International Conference on Attosecond Physics (ATTO3), held jointly in Sapporo, Japan, during July 3-8, showcased studies at the forefront of research on multiphoton processes and attosecond physics.