This book chapter provides an overview of the recent developments of III-nitride nanowire
heterostructures consisting of GaN, AlN, InN, and their alloys. The growth techniques and mechanisms for IIInitride
nanowires are first briefly reviewed, followed by detailed discussions on the structural, optical and
electrical transport properties of various III-nitride nanowire heterostructures. Special attention is paid to the
recent achievement of high quality InN, InGaN core-shell, as well as dot-in-a-wire nanoscale heterostructures.
The emerging device applications of III-nitride nanowires, including nanoscale transistors, LEDs, lasers, and
solar cells are presented, and the challenges and future prospects of III-nitride nanowires are also discussed.
Keywords: Nanowire, GaN, InN, AlN, light emitting diode, transistor, solar cell.