This paper reviews: (1) methods by which bond rupture, and ionization, can be produced in organic solids; (2) methods of detecting trapped reaction intermediates; (3) illustrative experiments dealing with the yields and the decay of trapped electrons and free radicals. Factors to be considered in deciding whether trapped electrons and radicals decay by random reaction with potential reacting partners, by combination with sibling partners, or by combination with other predestined partners are discussed. It is shown that radical decay rates do not show consistent correlation with viscosity.