Although evolutionary algorithms are very different from other artificial intelligence search algorithms, they face similar fundamental issues-representation and searching. There has been a large amount of work done in evolutionary computation on searching, such as recombination operators, mutation operators, selection schemes and various specialised operators. In comparison, research on different representations has not been as active. Most such research has been focused on a single representation, e.g. bit strings, real-valued vectors using Cartesian coordinates, etc. This paper proposes and studies multiple representations in an evolutionary algorithm and shows empirically how multiple representations can benefit searches as much as a good search operator could. © 2000 IEEE.