Recently, the alarming decrease of insect populations has received much attention, especially since the publication of a German study that showed strong decline of insects in nature reserves. Similar declines may be expected in the Netherlands, but many knowledge gaps exist about what we already know about the current situation and what influences the species composition of insects. This report aims to use information from an existing dataset to explore the species composition of insects in Dutch peat marchlands. The influence of habitat types and other environmental factors such as land use on the species composition was analyzed. Furthermore, the three different trapping methods used in this study were evaluated. This report thereby contributes to filling some of the existing knowledge gaps about Dutch insect populations and provides a number of recommendations for future monitoring of insects.