Demonstrates the wide scope of cycloaddition reactions, including the Diels-Alder reaction, the ene reaction, 1,3-dipolar cycloadditions and [2+2] cycloadditions in organic synthesis. The author, a leading exponent of the subject, illustrates the ways in which they can be employed in the synthesis of a wide range of carbocyclic and heterocyclic compounds, including a variety of natural products of various types. Special attention is given to intramolecular reactions, which often provide a rapid and efficient route to polycyclic compounds, and to the stereochemistry of the reactions, including recent and developing work on enantioselective synthesis.