This review is focussed on the crosslink distributions between rubber phases, which arise when blends of rubbers are vulcanized, how these distributions may be evaluated and controlled, and how they impact upon the properties of the blends. The blends are divided into three categories - rubbers differing primarily in polarity, rubbers differing primarily in degree of unsaturation, and rubbers differing little in either polarity or degree of unsaturation. Control of crosslink distribution is important if the best is to be obtained from vulcanized blends. When crosslinks are very unevenly distributed in a blend, improvement of the distribution leads to improved physical properties.