The two main reasons for tearing are epiphora and excess lacrimation. Epiphora is a result of a failure of tear drainage caused by mechanical obstruction or lacrimal pump failure. Lacrimation is excessive tearing caused by reflex hypersecretion. The goal of the basic examination is to distinguish between epiphora and lacrimation. The clinical history, palpation, inspection, diagnostic probing and syringing are sufficient to evaluate the function of the lacrimal drainage system or to determine location and extension of obstructions in most patients with epiphora. Numerous diagnostic tests are available and the most important tests and their interpretation are described.