The thermal properties of two series of AB di-block copolymers of poly(ε-caprolactone) (A) and poly(lactide) (B) and their blends were studied. Each series contained poly(lactide) blocks of opposite chirality. The length of the poly(ε-caprolactone) blocks was not varied (DP = 70), whereas the poly(lactide) blocks were of varying length (DP = 5 - 80). Blends of polymers containing blocks of opposite chirality were prepared by mixing in solution. The melting temperature of the PLA phase was raised by approximately 55 °C in the blends due to stereocomplex formation. The melting temperatures of the crystalline PCL and PLA phases strongly depended on the composition of the block copolymers.