Publisher Summary Fossil insects are often abundant in a wide range of Quaternary deposits. Several orders of insects can be found in fluvial and lacustrine sediments. This chapter focuses on remains of midges and beetles from the Quaternary period, especially the Late Pleistocene and Holocene, for the paleoenvironmental studies. Chironomidae belong to the Order Diptera: Nematocera and they are colloquially known as “non-biting midges.” The distribution of the different chironomid taxa is restricted by environmental conditions. Their remains are of special interest in paleolimnology because their strongly sclerotized larval head capsules are preserved in sediment deposits. There are several reasons for chironomids to be considered important in paleolimnology: (1) they are sensitive to environmental variables such as temperature, pH, trophic conditions, and dissolved oxygen; (2) they have relatively short life cycles; (3) the adult are mobile; (4) the larvae possess chitinous head capsules that are well preserved in lake sediments; and (5) they are abundant, diverse, and readily identifiable to generic and species-group level, enabling high resolution studies. Past chironomid stratigraphies can be reconstructed and readily used to infer environmental conditions at the time of deposition.