We examine the relative stability and adhesion of the polar Al(111)/WC(0001) interface using density functional theory. Relaxed atomic geometries and the ideal work of adhesion were calculated for six different interfacial structures, taking into account both W- and C-terminations of the carbide. The interfacial electronic structure was analyzed to determine the nature of metal/carbide bonding. Based on the surface and interfacial free energies, we find that both the clean WC(0001) surface and the optimal interface geometry are W-terminated. Although both terminations yield substantial adhesion energies in the range 4-6 J/m 2 , bonding at the optimal C-terminated structure is nearly 2 J/m 2 stronger, consistent with an argument based on surface reactivity. In addition, we examine the effects of Li and Mg alloying elements at the interface, and find that they result in a strain-induced reduction of metal-ceramic adhesion.