A 28-year-old interior designer, ZL, presented to her GP with a 12-month history of change in her appearance, excess facial hair growth and irregular, scanty periods. She had noticed that her cheeks were becoming fatter and that she was always red in the face, with the onset of greasy skin and acne more latterly. She had marked hair growth over her chin and upper lip. On questioning, she had gained weight ‘round the middle’ and noticed the development of red stretch marks on her abdomen. She generally felt very low about things. Physical examination suggested that she had Cushing’s syndrome and she was referred to the local endocrine clinic. When she arrived there, the above features were noted plus a marked proximal myopa- thy. Investigations revealed elevated urinary free cortisol levels, plasma cortisol concentrations of 1059nmol/L at 0900 h and 1003 nmol/L at midnight. The ACTH concentration at 0900h was 230 ng/L. Pituitary MRI scanning suggested an abnormality in the left side of the gland, and this was supported by bilateral catheterization of the petrosal sinuses with multiple ACTH measurements. She underwent trans-sphenoidal surgery with removal of a pituitary adenoma which stained strongly for ACTH on immunohistochemical testing. Postoperatively her symptoms resolved associated with normalization of her pituitary function.