The approach to the diagnosis and management of glaucoma has undergone considerable changes in recent years. Current concepts of glaucoma diagnosis focus on structural assessment and structure-function correlation, and relies less on the finding of visual field abnormalities. In turn, contemporary approaches to management have also changed and revolve around earlier initiation of pressure lowering medication based on pre-perimetric findings. This article presents an approach to the assessment of the patient with suspected glaucoma, highlighting those structural and ancillary diagnostic investigations that will aid in the correct diagnosis. It also discusses the differentiation of glaucoma from other, non-glaucomatous disease processes.