Blends of the aliphatic polyester poly(epsilon-caprolactone) with two biphenyl-containing polyesters have been investigated. The aromatic polyesters differed in the number of phenyl groups incorporated in the repeating unit; in this way a semi-rigid liquid crystalline and a semicrystalline polyester were obtained. Blends of the aromatic polyesters with poly(epsilon-caprolactone) were prepared by the dissolution/precipitation method and characterized by optical microscopy, d.s.c., small-angle laser light scattering and X-ray diffraction. A marked difference in crystallization behaviour and crystallinity was observed, although melting and crystallization temperatures were not influenced by changing the composition of the blends. The experimental results indicate the occurrence of miscibility phenomena in the isotropic state of blends of poly(epsilon-caprolactone) with the most flexible biphenyl-containing polyester.