Hidradenitis suppurativa (HS) is an inflammatory skin disease that has many phenotypes. In daily practice, the Hurley stages are frequently used to classify HS. A major shortcoming of the 'classic Hurley classification "is not included the inflammatory component and the extent of HS. For these reasons, the Working Group HS an aside nuances recently made to the 'classic Hurley classification. The nuances, this "sophisticated Hurley classification" the ability to characterize the different phenotypes HS nauwkeurigte. In addition, the working group on the basis of the 'refined Hurley classification' a treatment algorithm developed based on recent guidelines. The handy app allows the 'refined Hurley classification "by applying the appropriate treatment algorithm in daily practice.