Dilute nitride alloys are a novel set of semiconductor alloys, of

interest both from a fundamental perspective and for awide range of

potential applications. Their properties are markedly different from

those of conventional alloys such as GaAs. This chapter presents

an overview of the unusual electronic structure of dilute nitride

alloys. We first describe that the band-anticrossing model provides

a good basis to understand the electronic properties of alloys

such as GaNAs and GaInNAs. We then apply the band-anticrossing

model, with suitable modifications, to analyze the key features of

the electronic structure. Finally we discuss the consequences of the

unusual electronic structure for the observed transport and optical

properties and for selected device applications.