During a one-year period 53 patients were referred for the investigation of epiphora. All underwent bilateral dacryoscintigraphy. Following the isotope study the patients had either bilateral or unilateral macrodacryocystography; a total of 66 tear ducts were shown by this procedure. The scintigraphs were more sensitive for obstruction (51/66 systems or 77%) than radiography (33/66 systems or 51%). Normal dacryoscintigraphy was always associated with duct patency on dacryocystography. We have concluded that scintigraphy should always be the first investigation and that, if this is normal, radiography is not necessary. The use of digital subtraction imaging for the lacrimal passages is discussed. It is suggested that this may provide information obtained at present only by combining dacryoscintigraphy with conventional contrast radiography.