Spectral and directional control of thermal radiation is a challenging yet important task for a number of applications, including thermophotovoltaic energy conversion, solar energy utilization, space thermal management, and high-efficiency incandescent lamps. A number of structures have been proposed as coherent emission sources, with spectral emission peaks in well-defined directions. The grating structure has been commonly used in which coherent emission is achieved by the excitation of surface polaritons or surface waves. Along with the development of metamaterials, magnetic polaritons have received much attention lately. Furthermore, planar structures can also support surface waves or optical resonance for thermal emission control. This presentation will give an overview of our recent theoretical and experimental research results in controlling the spectral and directional thermal radiative properties using subwavelength periodic gratings, truncated photonic crystals, Fabry-Perot optical cavities, vertically aligned carbon-nanotube arrays, and metamaterials.