The interest and level of research into climate variability has risen dramatically in recent years, and major breakthroughs have been achieved in the understanding and modelling of seasonal to interannual climate variability and prediction. At the same time, the documentation of longer term variability and its underlying mecha- nisms have progressed considerably. Within the European Commission’s Environment and Climate research programs several important projects have been supported in these areas – including the "Dec- adal and Interdecadal Climate variability Experiment" (DICE) which forms the basis of this book. Within the EC supported climate research, we see an increasing importance of research into climate variability, as is evidenced in the upcoming Fifth Framework Programme’s Key Action on Global Change, Climate and Biodi- versity. This is because of the obvious potential socio-economic benefits from sea- sonal to decadal scale climate prediction and equally important for the fundamental understanding of the climate system to help improve the quality and reliability of future climate change and mankind’s current interference with it. The DICE group has performed important and pioneering work, and we hope this book will receive the wide distribution and recognition it deserves. We wel- come the contributions from distinguished researchers from US, Japan and Canada to the EC’s DICE group towards completing the scope of the book and as an exam- ple of international cooperation which is essential in such a high-level scientific endeavor.