  This text will appear as Section II of Chapter 5 of the book "Black Holes in
the Era of Gravitational-Wave Astronomy". As a stand alone text, it serves as a
brief overview of astrophysics and gravitational wave radiation of extreme mass
ratio inspirals, or EMRIs. Topics covered consist of: dynamical and
gas-assisted formation channels, basics of EMRI dynamics and gravitational
radiation, and science potential for both astrophysics and fundamental physics.
