The problem of determining the two-dimensional steady-state temperature field in a bimaterial with a curved microscopically imperfect interface is considered. The temperature jump across the interface is proportional in magnitude to the interfacial heat flux. The conditions on the interface are formulated in terms of a boundary integral equation containing both Cauchy principal and Hadamard finite-part integrals. A numerical method based on this formulation is outlined for the numerical solution of the problem under consideration. It is applied to solve some specific problems. Copyright (C) 2007 John Wiley & Sons, Ltd.