The negative effects of alien introduced species on the composition and ecology of native communities have been widely reported as their impacts on human health and economy. Much effort has been spent to identify factors that contribute to the success of invaders. The knowledge of the mechanisms underlay the invasion process may help the prediction of further invasion and give the tools for the management and control of the current invasive species. Phenotypic plasticity has been repeatedly suggested among the traits associated with invasion. To investigate the role of phenotypic plasticity in plant invasion we will examine the invasive strategy of Impatiens species both invasive and native to Britain and Europe. Impatiens noli-tangere is native to continental Europe and Britain, Impatiens glandulifera is currently one of the dominant invasive plant species in Europe. In addition, we will use three other exotic Impatiens species naturalized in Europe that vary in their invasive capacity (I. capensis, I. parviflora and I. balfourii).