With the use of genetic engineering technology, it is feasible to manipulate a plant's capacity to tolerate, accumulate and metabolize metal pollutants, and hence create ideal plants for environmental cleanup. If we know which molecules are involved in these tolerating and accumulating processes, and which genes control these mechanisms, we can manipulate them to our advantage. This review aims to give a succinct overview of plants' metal tolerance and accumulation mechanisms, to identify possible strategies for genetic engineering of plants for metal phytoremediation, and to present an introduction to what has been achieved so far regarding manipulation of metal metabolism in plant.