The spread of invasive alien species (IAS) is creating complex and far-reaching challenges that threaten both the natural biological riches of the earth and the well being of its citizens. Summarising key findings of the Phase I Synthesis Conference held in September 2000 in Cape Town, Republic of South Africa, this publication presents ten strategic responses that address how to mitigate the threats of IAS. Directed toward the decision-makers whose policies and practices are affecting the movement of species around the world, this strategy strives to provide a resource to increase awareness and provide policy advice.