Cylindrical vector beams have been proposed and demonstrated for applications ranging from microscopy to high energy physics.In this paper,we analyze the three-dimensional field distributions of radial and azimuthal beams focused near a dielectric interface.We give particular attention to the classic problem of high numerical aperture focusing from an immersion lens to a glass-air interface and find that the use of radially and azimuthally polarized illumination for this type of imaging provides an impressive lateral confinement of the fields over a wide range of interface positions.