This paper describes some recent experiments on the stability of cylindrical converging detonations in a gaseous explosive. Perturbations are generated on the symmetrical detonation front by placing a cylindrical rod in its path. Observations of the phenomenon are obtained by spark schlieren photography. Iy was found that converging detonations are stable in the sense that there exists a curvature distribution mechanism whereby local perturbations are distributed by a set of transverse pressure waves propagating tangentially to the front. Provided these disturbances are created before significant cumulation behind the converging front has occurred, the amplitudes of the transverse waves are found to decay rapidly with travel and the front regains its former symmetry.