Chronic inflammation comprises a vast array of diseases that affect millions of people worldwide. Chronic inflammatory diseases include asthma, arthritis, atherosclerosis, Alzheimer’s disease, autoimmune diseases and allergies, to name but a few. A common theme to all of the above diseases is that the inflammatory response, originally aimed at recognizing and eliminating foreign “pathogens” or damaging agents, overreacts to them and causes tissue damage that can be detrimental to the patient. How to limit such overreaction without compromising the efficiency of the inflammatory response is a phenomenal challenge faced by scientists and clinicians working in this field. Our current therapeutic tools, in particular anti-inflammatory drugs and steroids, fall short of accomplishing such a task as they can decrease the patient’s natural defense mechanisms and produce a host of undesirable side effects. The scientific goal of the MAIN Network of Excellence is to identify and characterize the molecular mechanisms underlying chronic inflammatory responses, with emphasis on a crucial step in such responses, namely the transmigration of leukocytes (“white blood cells”) from the bloodstream into inflamed tissues and their local activation by inflammatory substances and pathogens. To achieve this goal, MAIN has gathered over 150 researchers and graduate students from 13 research institutes and 2 biotechnology companies of five EU member states as well as Switzerland and Israel. MAIN will be co-funded by the EU with a 10 M€ grant over a four year period. The international dimension of MAIN is further emphasized by the strong connection existing between MAIN scientists and the US Cell Migration Consortium (CMC), whose goal is to explore the complex mechanisms underlying cell migration in embryonic development, wound healing and cancer. MAIN and CMC will share information and technology platforms and will develop a coordinated agenda of scientific events in order to communicate their scientific achievements to a wider scientific audience as well as to the general public.