Gold(I)-phosphine complexes are readily encapsulated by a tetrahedral supramolecular host (Ga(4)L(6)). We have investigated the catalytic activity of the resulting complexes for the intramolecular hydroalkoxylation of allenes. The catalytic activity of Me(3)PAuBr was increased 8-fold by encapsulation, as determined by initial rate kinetics, and we observed up to 67 catalytic turnovers by Me(3)PAu(+) encapsulated in Ga(4)L(6).