In The Geometrid Moths of Europe, Volume 2 on Sterrhinae, a number of difficult genera such as Cyclophora, Scopula and Idaea are covered. Especially Idaea with more than 100 species occuring in Europe, has caused a lot of problems to identify, but based on the many specimens illustrated on the 24 colour plates, the species of this genus can be identified much easier now. Apart from its largest species, the genus Idaea is illustrated in 1.5 times natural size. The remaining Sterrhinae are in natural size on the colour plates. On additional black and white photos for species which are difficult to identify, their differential characters are pointed out with arrows. Three new species and three new subspecies are described. A map with the European distribution is given, and with dots for verified specimens. Finally there are line drawings of male and female genitalia of all species and also this volume contains a systematic catalogue of the European species and including those of the neighbouring regions such as North Africa, Macaronesia, Turkey, and the Middle East.