Indenyl zirconocene dinitrogen complexes were synthesized from the direct activation of N2 by isolable cyclopentadienyl η9 indenyl zirconocene sandwich complexes, (η5-C5Me5)(η9-C9H5-1-R-3-Me)Zr (R = Me, CHMe2, CMe3), or from the alkali metal reduction of the corresponding zirconocene dihalide under dinitrogen. In the former, dimeric weakly activated end-on dinitrogen complexes with η5,η2 indenyl ligands, [(η5-C5Me5)Zr]2 μ2-η2,η2-{4,5-(η5-C9H5-1-R-3-Me)}2, were synthesized. In the latter, dimeric modestly activated side-on, end-on dinitrogen complexes with an η5,η4 indenyl ligand, [(η5-C5Me5)Zr]2 μ2-η5,η4-(η5-C9H5-1-R-3Me) (μ2-η1,η1-Cl), were isolated. The alkali metal reduction of a series of bis(indenyl) zirconocene dihalides under N2 furnished dimeric strongly activated end-on dinitrogen dianions, [(η5-C9H5-1-CHMe2-3-Me)(η5-C9H5-1-CHMe2-3Me)Zr(NaX)]2(μ2-η1,η1-N2) (X = Cl, Br, I), which readily hydrogenate yielding the corresponding zirconocene hydrazido hydride complexes with a side-on bound hydrazide, [(η5-C9H5-1-CHMe2-3-Me)(η5-C9H5-1-CHMe2-3-Me)ZrH]2(μ2-η2,η2N2H2). Due to the propensity of hafnium to attain its highest oxidation state, dinitrogen activation chemistry was not observed for indenyl hafnocene complexes, although several η6,η5 bis(indenyl)hafnium (II), along with hafnocene (III) species were isolated. The reduction of a series of ansa-zirconocene complexes with [CH2CH2], [Me2Si] and [Me2C] bridges was also explored. Zirconocene diiodide compounds with Me2E(η5-C5H3-3-R’)2 (E = Si, R’ = CMe3; E = C, R’ = SiMe3, CMe3) ligands furnished strongly activated side-on bound dinitrogen complexes when treated with excess 0.5 % sodium amalgam under an atmosphere of N2. Exposure of dihydrogen furnished the expected zirconocene hydrazido hydride complexes. However, the hydrazide readily underwent dehydrogenation, even under one atmosphere of H2, affording hydrido zirconocene dinitrogen complexes Me2E(η5C5H3-3-R’)2ZrH]2(μ2-η2,η2-N2). In the course of developing zirconium-promoted Pauson-Khand chemistry, the addition of ketones to η9 indenyl zirconocene complexes showed divergent product formation: either yielding a zirconocene enolate hydride or insertion of the carbonyl into the indenyl ligand. In the former, a haptotropic rearrangement of the indenyl ligand from η9 coordination to η5 occurred, while in the latter rearrangement to η1, η3, η5 or η6. Mechanistic studies demonstrated that pKa, steric bulk and concentration of the ketone reagent are important to the reactivity.