Surfactant-templated binuclear alkoxysilane precursors or cyclic silsesquioxane precursors have led to a new class of nanocomposites with bridging organic groups (R) inside the channel walls, known as periodic mesoporous organosilica (PMO). These PMO materials facilitate chemistry of the channels and provide new opportunities for controlling the chemical, physical, mechanical, and dielectric properties of the materials. This review provides an overview of recent papers on the synthesis of PMOs and their applications as catalysts published after the year 2000.