This chapter describes many of the skin diseases associated with diabetes, thyroid, pituitary, and sex hormone disorders and includes some useful treatment tips and clinical images. Diabetic reactions include skin infections, granuloma annulare, necrobiosis, eruptive xanthomas, and insulin injection site reactions. Brief descriptions of skin problems encountered in hyper- and hypothyroidism are included. The rarer but important skin changes seen in pituitary disorders such as Cushing’s syndrome, Addison’s disease, and acromegaly are described. The role of androgens on the skin and problems created from androgen or oestrogen deficiencies/excess are elaborated. The very rare polyglandular autoimmune type 1 and multiple endocrine neoplasia syndromes are also briefly discussed.