1. Serial extraction of West Indian mahogany wood with selective solvents was performed. 2. The petroleum ether extract was the only fraction to exhibit promising termite-repellent activity. 3. Mahogany blocks subjected to petroleum ether extraction became susceptible to termite attack. 4. A waxy substance (P2 fraction) separated from the petroleum ether extract at times showed high termite-repellent activity. The termite-repellent principle in the P2 fraction seems to be a labile one, as the termite-repellent activity varied greatly from batch to batch. 5. The P2 fraction is a mixture of two major components and of at least a third minor one. As far as we have been able to determine this mixture, at the elemental level, contains carbon, hydrogen, and oxygen only, while esters have been the only compounds definitely characterized at the structural level.