The conservation of forest genetic resources is regarded as an important contribution to sustainable forest management and the preservation of biological diversity in Switzerland. Close-to-nature silviculture and in particular natural regeneration are widely practiced in Switzerland and contribute to the conservation of forest genetic resources. Reproductive material for artificial regeneration is mainly harvested in phenotypically selected seed stands. Locally adapted tree populations are conserved in in situ gene reserves. Criteria for the selection of gene reserves are described Variation patterns at genetic markers are of extraordinary significance for the selection of gene reserves in Switzerland The establishment and silvicultural management of a network of gene reserves aims at the preservation of genetically variable and differentiated populations for the main tree species. Gene reserves are currently establishedfor Norway spruce (Picea abies (L.) Karst), silver fir (Abies alba Mill.), and native oaks (Quercus spp.). More research is needed with regard to patterns of adaptive genetic variation of tree species, the assessment and conservation of genetic variation of rare species, and the observation of the temporal dynamics of genetic structures in tree populations.