The unitary dual and the wavefront set form fundamental problems in the representation theory of reductive algebraic groups over local fields. In this talk, I will explain recent progress based on the fundamental work of J. Arthur and others. The relevant results are mainly from my joint work with A. Hazeltine, B. Liu, C.-H. Lo, and Q. Zhang, with B. Liu, C.-H. Lo and L. Mason-Brown, and with C. Chen, D. Liu, and L. Zhang.