In contrast to ketones, one of the most important classes of organic compounds, their heavier element congeners, "heavy ketones", are much less explored because of their extremely high reactivities. This Account reviews the synthesis, reactivities, and structures of stable heavy ketones containing silicon, germanium, and tin as well as those of moderately stable lead analogues. These heavy ketones are kinetically stabilized by taking advantage of bulky substituents, yet they can undergo a variety of reactions due to the intrinsic high reactivity of heavier group 14-16 double bonds. Systematic comparisons for silicon through lead compounds reveal interesting differences in their properties, depending on the elements.