The tetracyclic diterpene waihoensene has been identified in some specimens of Podocarpus totara, particularly in a varietal form, P. totara var. waihoensis. We detail the structural analysis of this unique compound by nuclear magnetic resonance (NMR) correlation experiments, and describe some chemistry conducted on a previously reported tetracyclic alkene, the product of acid-induced rearrangement of the fenestrane diterpene lauren-1-ene. This work establishes an interrelationship between the triquinane structures of laurenene and waihoensene.