A review is given of the history of one of the most interesting phenomena in high-energy physics, namely, diffraction dissociation (DD) of hadrons. It was predicted more than 50 years ago by Pomeranchuk and Feĭnberg and has for many years occupied an important place in experimental high-energy studies on major accelerators across the world. This review presents a reasonably complete account of the main experimental results and of the more ``settled'' theoretical models of DD. Although the discussion is mostly restricted to single nucleon DD, it nevertheless provides a basis for a relatively complete description of this phenomenon. The historical approach adopted in this review to experimental studies of DD is emphasized by numerous references to pioneering work. The last part of the review is devoted to the leading experimental results on DD, obtained during the last five years and not covered by previously published reviews. The new experimental data reveal sufficiently clear evidence for the parton structure of the excited system and of the pomeron. It is emphasized that an understanding of the DD mechanism is crucial to the solution of the confinement problem in the theory of strong interactions, and requires further experimental and theoretical investigation.