The highly electrophilic, coordinatively unsaturated, 16-electron [Ru(P(OH)(3))(dppe)(2)][OTf](2) (dppe = Ph2PCH2CH2PPh2) complex 1 activates the H-H, the Si-H, and the B-H bonds, in H-2(g), EtMe2SiH and Et3SiH, and H3B center dot L (L = PMe3, PPh3), respectively, in a heterolytic fashion. The heterolysis of H-2 involves an eta(2)-H-2 complex (observable at low temperatures), whereas the computations indicate that those of the Si-H and the B-H bonds proceed through unobserved eta(1)-species. The common ruthenium-containing product in these reactions is trans-[Ru(H)(P(OH)(3))(dppe)(2)][OTf], 2. The [Ru(P(OH)(3))(dppe)(2)][OTf](2) complex is unique with regard to activating the H-H, the Si-H, and the B-H bonds in a heterolytic manner. These reactions and the heterolytic activation of the C-H bond in methane by the model complex [Ru(POH)(3))(H2PCH2CH2PH2)(2)][Cl][OTf], 4, have been investigated using computational methods as well, at the B3LYP/LANL2DZ level. While the model complex activates the H-H, the Si-H, and the B-H bonds in H-2, SiH4, and H3B center dot L (L = PMe3, PPh3), respectively, with a low barrier, activation of the C-H bond in CH4 involves a transition state of 57.5 kcal/mol high in energy. The inability of the ruthenium complex to activate CH4 is due to the undue stretching of the C-H bond needed at the transition state, in comparison to the other substrates.