This paper describes the design of a low power MPEG-1 motion vector reconstructor using behavioural synthesis methodology. Various techniques, such as appropriate voltage scaling after clock and operations throughput selection, and reduction of multiplexer-based interconnection complexity are used to reduce power consumption. The design has been implemented based on a library components previously synthesised using Synplify ASIC w design has been performed through timing simulation with ModelSim, whereas power analysis is based on the reports obtained with PrimePower from Synopsys. The proposed design dissipates 42% less power than a power unaware design operated at the maximum supply voltage of the library components, i.e. 1.32V.