Cyclical Cushing’s syndrome, characterised by intermittent biochemical hypercortisolism, accounts for approximately 20% of endogenous Cushing’s syndrome. Cycles may last days to years, often with intraindividual consistency, suggesting an intrinsic fault in timekeeping although a unified molecular cause is yet to be found. Affected individuals may be either normocortisolaemic or hypocortisolaemic between episodes. Cylicity may arise in any aetiological form of Cushing’s syndrome, and should be suspected if there is clinical and biochemical fluctuation or discordance. Cyclical Cushing’s syndrome complicates the assessment, diagnosis, management and long-term monitoring of the condition as will be covered during this practical talk on lessons learnt from the multidisciplinary pituitary clinic.