This chapter provides the top quality images of ichthyosis vulgaris with horn layers, reduced granular layer and prominent granular layer, to correlate clinical presentations with histopathologic slides. Annotated images highlight subtle indications that can clinch the diagnosis. The chapter presents other diagnosis such as refsum syndrome, X-linked dominant ichthyosis, lamellar ichthyosis, and bullous epidermolytic ichthyosis. The clinical symptoms and biochemical findings of ichthyosis and deafness syndromes are also provided.