Introductory Overview articles are designed to provide introductory level background to key themes and topics that caters to the eclectic readership of EMS. It is envisaged that these articles will help to break down barriers to shared understanding and dialogue within multidisciplinary teams, and make environmental modelling more accessible to a wider audience. Relevant concepts are presented in relatively simple terms, with the audience assumed to have some basic knowledge of environmental modelling and mathematics. Introductory Overviews are directed specifically at the EMS audience and undergo formal peer review. Introductory Overviews are by invitation only. Ideas for Introductory Overviews can be canvassed with one of the Editors. The first Introductory Overview, which provides a primer on the dimensions of Integrated Assessment and Modelling, is published in this issue.