Abstract Compounds of the helium‐group gases, known since 1962, are limited to those of xenon, krypton, and radon. These heavy noble gases form stable compounds and adducts with fluorine and other powerful oxidants. Xenon has the best studied, most extensive chemistry. The oxidation states observed for xenon range from $${+}$$ to $${+8}$$ . Bonds to fluorine, oxygen, nitrogen, and carbon have been characterized. The chemistry of krypton, which has one known oxidation state, $${+2}$$ , is far less extensive, but bonds to fluorine, oxygen, and nitrogen have been characterized. That of radon is even less well characterized and is limited to fluoride species of the $${+2}$$ oxidation state. Properties of the compounds are reviewed.