Abstrset. A basic elasticity solution applicable to an important class of internal stress problems related, for example, to fiber-matrix composites and spalling of cylindrical coatings is obtained. The basic problem that has been solved is that of the slnsular stress-displacement field resulting from the introduction of a Somigliana ring dislocation in an isotropic linear elastic solid. The Burgers vector of this dislocation has two components, one being normal to the plane of the circular ring dislocation (Vulterra type) and the other being in the radial direction of the ring dislocation everywhere (Somigliana type). The analytical solution, in terms of complete elliptic integrals of the first, second and third kinds, is obtained using the Love stress function and Fourier transform. The results are verified numerically and by examining various limiting cases, including the straight edge dislocation as the radius of the dislocation loop tends to infinity, the orthogonal pair of dipoles as the radius tends to zero, and the Lam~ solution of a cylindrical bar and a cylindrical hole in an infinite medium as the axial location of the dislocation tends to minus infinity. The resulting analytical solution is considered as a step towards evaluating both the extended stress field around and interactions among various three-dimensional defects such as cylindrical cracks, fiber-tips and fiber-matrix debonding. AMS mbjeet ~tioa (19~0): 73S05. List of symbols ~b = Love stress function a, = Radial stress ~o = Transveric stress a~ = Axial stress a,z = Shear stress u = Radial displacement w = Axial displacement z, r = Axial and radial coordinates v = Poisson's ratio G = Shear modulus of elasticity b = Burgers vector b~ --Radial Burgers vector b2 = Axial Burgers vector R = Radius of ~ircular dislocation loop ~ = Fourier transform variable Io, 11 = Modified Bessel functions of the first kind Ko, KI = Modified Bessel functions of the second kind K('), E(.), II(.) = Complete elliptic integrals of the first, second and third kind, respectively. A = 4 × 3 matrix B = 2 × 2 matrix H(') = Heaviside step function 6(') = Dirac delta function