Organics are a significant component of most cosmic dust, as revealed from actual samples of extraterrestrial dust in the Earth’s stratosphere, in Antarctic ice and snow, in near-Earth orbit, and in asteroids and comets. Cosmic dust contains a diverse population of organic materials that owe their origins to a variety of chemical processes occurring in many different environments. The presence of isotopic enrichments of D and 15N suggests that many of these organic materials have an interstellar or protosolar heritage. The study of these samples is of considerable importance because they are the best preserved materials of the early Solar System available.