Structure and Kinematics of Emission Line Regions in AGN

I will review some key aspects of the physical conditions of the line emitting regions in AGN.The innermost BLR extends at radii of light days to light weeks from the central ionizing source.There are strong indications that the BLR clouds are connected to the outer region of an accretion disk.Trends of radial acceleration of the line emitting clouds have been found in the extended narrow line region.Ⅰ will concentrate on observations taken in the optical wavelength range.Finally, Ⅰ will discuss different methods to determine the mass of the central supermassive black hole from the emission lines.