Of late Gold catalysis are applied in heterogeneous and homogeneous processes including hydrogenation, hydrosilylation and nucleophilic functionalisation of unsaturated substrates. But the mode of action of these important catalysts remains speculative as intermediates are difficult to observe. In Gold Hydrides this is due to mismatch between the oxidizing nature of gold cations and reducing character of the hydride ligand. We have recently synthesised a range of Au(III) hydrides as models of these intermediates, but polydentate ligands are required to stabilse them and this hampers catalytic activity. Exciting developments to overcome this have been achieved by designing a route to hydride-like Au (I) adducts that 'bridge' two metal centres, but spectroscopic and X-ray measurements cannot determine the nature of this bonding and thereby gain insight into catalytic behaviour.