The mitigation of habitat fragmentation due to transport infrastructure is a relatively new field of knowledge, which combines engineering and ecology. The way infrastructure is placed in the landscape can be of great importance to wildlife. The handbook describes various factors that should be considered both in the planning of transport corridors and the integration of infrastructure in the landscape. Emphasis is placed on the building of fauna passages, over- and underpasses, pipes, culverts and bridges for several different species.

Partly due to different traditions, and partly due to different physical and ecological contexts, the design of fauna passages and other mitigation measures differs between countries. As a result, there are few general formal standards for the design, construction and maintenance of mitigation measures in Europe. To date, few evaluations of mitigation measures have been carried out. Further work is needed, including studies of the effects of measures at the population level. Based on experience and the evaluation of alternative structures, designs can be improved and eventually standards can be formulated. The ongoing exchange of knowledge and experience across Europe and beyond is necessary to develop these new standards.