This review covers a wide range of palladium-catalyzed processes involving oxidation addition/reductive elimination chemistry. Topics discussed include palladium chemistry, heterocycles via palladium-catalyzed oxidative addition reactions, heterocycles via alkene cyclizations, heterocycles via cyclization and annulation of alkynes, heterocycles via carbonylative cyclization, heterocycles via palladium-catalyzed aryl/vinylic amination, and heterocycles via palladium-catalyzed intramolecular biaryl cross-coupling.