Hysteroscopy can be used to diagnose endometrial and structural cavity pathologies associated with abnormal uterine bleeding (AUB) and reproductive failure. Optimal interpretation of hysteroscopic findings requires an understanding of the limitations of the technology and incorporation of information obtained from the preceding clinical history and examination. Ideally, hysteroscopy should be avoided during the menstrual period, as the obtained views are likely to be compromised. Although normal endometrial appearances during the secretory phase could potentially be misinterpreted (e.g. as polyps or hyperplastic endometrium), with experience the likelihood of this is small, and so timing the procedure to coincide with the proliferative phase of the menstrual cycle is not necessary or indeed practical