AOR, short for Adult Oriented Rock, is a sub-genre of Rock that emerged in the late 1970s and early 1980s as an amalgamation of Hard Rock, Pop Rock and Progressive Rock. It is characterized by a rich, layered sound, slick production and a heavy reliance on commercial melodic hooks, which led to its huge popularity in the late 1970s and early 1980s. Adult-oriented rock is commonly conflated with but distinguished from the US "album-oriented rock" FM radio format, also called AOR, which played not only adult-oriented rock but also album tracks and "deep cuts" from a variety of other rock genres.

AOR songs are almost always electric guitar and synthesizer-driven, occasionally crossing over with other popular synth-driven genres such as Synthpop and New Wave, very often including harmonized vocals. The catchy, singalong choruses combined with relatively short song lengths and a bombastic, anthemic quality modeled after prog’s theatrical ambitions make AOR a very radio-friendly genre. The songs are typically more melodic than most straightforward hard rock, but harder edged than most pop rock, not unlike Power Pop‘s marriage of sugary harmonies and muscular, driving riffs.

Some of the earliest and most well known AOR bands include names like Asia, Boston, Foreigner, Journey, Survivor and Toto, with songs such as Boston's "More Than a Feeling" and Toto's "Africa" becoming hugely popular radio staples, the latter showcasing influences from lighter pop rock stylings more akin to Soft Rock and Yacht Rock. As many of these bands are known for their stadium-filled shows, there is a significant overlap between AOR and "arena rock", an originally pejorative term used by critics to describe bands known for their crowd-pleasing anthems and power ballads. However, arena rock is not an AOR-exclusive term as many acts pegged as arena rock such as the Post-Punk rooted U2 come from many different backgrounds of rock music beyond AOR.

Although AOR experienced a decline in popularity in part due to the breakthrough of Alternative Rock in the 1990s, the genre eventually went through an underground resurgence in the 2000s with acts such as Brother Firetribe and Place Vendome reviving AOR’s pompous, arena-sized rock for the modern day.