DESCRIPTION: The three volumes that constitute this trilogy of Clues to Diagnosis in Dermatopathology are exemplars of sherlockian dermatopathology in which a reader is invited, in the manner of that master of deduction, the physician/logician, Arthur Conan Doyle, to take note carefully of clues (in this instance, certain histopathologic findings) for the purpose of apprehending a culprit (in this case, coming to a diagnosis with specificity). The format is the same in each of the three volumes, all of which portray clinical lesions and histopathologic attributes in vibrant color as follows: on the opening right hand page is a photomicrograph beneath which the question is posed, What is the Clue and what is your Diagnosis?; the page is turned and on the reverse of it are three photomicrographs, aligned vertically, one of which is the very same one that shows the clue to best advantage and that was pictured on the previous page, displaying the crucial histopathologic changes at scanning, intermediate, and high magnification, alongside one of which is set forth in print, crisply and lucidly, the clue to diagnosis and the diagnosis itself; an essay that illuminates the clue and the diagnosis is found on the third page, and Differential Diagnosis or Subtle Variations on the theme is illustrated by clinical photographs and photomicrographs, each of which is elucidated by a pithy legend, on the fourth and last page. Each volume consists of 100 clues. It is not hyperbolic to assert that if a student is conversant with the 300 clues and the diagnoses they help enable, proficiency in diagnostic dermatopathology in large measure is attained.