This guide to Chironomidae larval remains from lake sediments in the Western and Eastern Carpathians is a result of decades of passionate research, and hundreds of fieldtrips to mountain lakes in Slovakia, Poland, Ukraine, and Romania. These lakes situated in a fascinating scenery of the Carpathians Mountains are not only breathtakingly beautiful but also important for paleolimnological reconstructions of past nature processes. The guide brings identification keys for over 100 chironomid taxa from six subfamilies recorded in more than 70 lakes. The species, morphotypes and genera, documented with numerous photos, follow up-to-date taxonomy and they are preceded by a general introduction on the area of focus as well as the history of chironomid research in the Carpathians. Ecological knowledge and most plausible palaeoecological interpretations are summarized for every genus/morphotype.The Subfossil Chironomidae of the Western and Eastern Carpathians is a essential handbook for chironomid fanatics, teachers and students of aquatic ecology and palaeoecology, but also for ecologists, and conservationists working in the Carpathians.