Nitride alloys of Ga, In, and Al activated by rare-earth ions ( Re3+ ) are being considered for application in nitride-based solid-state light sources. The potential applications involve using such materials as the active layer in a heterostructure design or as a fluorescent material for converting the emission from a light-emitting diode to white light. In this paper, we report luminescence from Tm3+, Tb3+, Eu3+, and Tb3+ -Eu3+ couple in AlN powder samples synthesized for this purpose. Using the photoluminescence and photoluminescence excitation responses of Re3+-doped AlN samples, the multiplet structures of these Re3+ ions in AlN with tetrahedral coordination have been determined. The excitation energy transfer processes from the host and defects to Re3+ and from Tb3+ to Eu3+ have been observed. These processes are critical for developing nitride-based luminescent materials for white-light emission. (c) 2007 The Electrochemical Society.