Late in 2003 some members of our paleoeoclogy group found that an intensification of our information exchange would be welcome. In the beautiful Youth Hostel of Solothurn we organized a retreat of two days.

The first days all diploma students, all doctoral students and the postdocs presented their projects – a very full day! Emphasis was: where can I cooperate with my colleagues?

The second day started wit a brain storming: what topics am I mostly interested in? Out of this colourful flower bunch we grouped three main questions:

1. The 20^th century – its changes in vegetation, land-use and climate,
2. The Holocene variability in vegetation and climate – a new subdivision of the Holocene?
3. What was a tree refuge in the Ice Age? “Why did trees migrate so fast?”