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A broad-line region (BLR) is present in all AGNs accreting at moderate- to high-Eddington ratios. BLRs are important both because they are our best probe of how AGNs work and because of their potential for readily providing masses of supermassive black holes (SMBHs) back to the earliest times of galaxy formation. However, in order to be able to use BLRs to reliably estimate the masses of SMBHs it is essential to understand the structure and kinematics of BLRs. Over the last four decades there have been wide-ranging and, not infrequently, mutually contradictory views of the nature of the BLR (see reviews by Mathews & Capriotti 1985, Osterbrock & Mathews 1986, and Sulentic et al. 2000). However, I believe that the situation is improving. I review here what I consider to be the clearest pointers to the underlying structure and kinematics of the BLR and I argue that, while there are certainly many interesting problems remaining, the basic picture is now becoming fairly secure. I furthermore believe that this picture applies to all BLRs because BLR equivalent widths and line ratios are remarkably similar, especially in the ultraviolet.