Stephen Gourley recently made a two week visit to Hong Kong Polytechnic University to initiate new collaborative projects with mathematicians there. He worked with Professor Yijun Lou on the mathematical modelling of invasive weeds and pests. The project is motivated by the fact that these weeds and pests live outside their native territories and are therefore not kept in check by competitors and natural predators with which they co-evolved in their home territories.  Increased international trade makes this a significant concern because it carries the risk of introduction of exotic pests. Stephen will also be collaborating with Professor Daihai He on infectious disease modelling with particular emphasis on avian influenza in the Asia-Pacific region.