In dissociative recombination, a molecular ion captures an electron and fragments into atoms, molecules or ions. Dissociative recombination plays an important and often dominant role in many low to moderate temperature plasmas found in planetary ionospheres, the interstellar medium, fusion devices, laboratory experiments, and the region near reentry vehicle heat shields. The process has been studied for over 50 years but many of its mechanisms and those of competing processes have only been elucidated recently. Indeed, the study of dissociative recombination has been a challenge for both...