Under the supervision of P. Kleihues and L. H. Sobin, the "World Health Organisation Classification of Tumours" with its numerous volumes is currently being re-edited. Following the first three volumes on "Central Nervous System", "Digestive System" and "Haematopoetic System", the volume on "Tumours of the Breast and Female Genital Organs" will be published this autumn. This volume will be edited by F. Tavassoli and P. Devilee. The new WHO books serve a double function of text books and atlases of tumour pathology. The first part of the new volume includes the genetics and pathology of the entire spectrum of malignant tumours and their precursor lesions. The following part is devoted to benign proliferative lesions.