Editorial for the Special Issue on Cycloaddition Reactions at the Beginning of the Third Millennium

Cycloadditions are among the most efficient chemical processes because they combine atom economy and high levels of selectivity—particularly regio- and stereoselectivity—with the ability to generate molecular complexity in a single step [1]. The application of this methodology in various chemical fields remains highly relevant and effective [2], as substantiated by this Special Issue, which comprises eight experimental articles and three reviews addressing this subject