The present invention relates to methods and assays for identifying agents capable of modulating GPR84 activity in cells, in particular agents that inhibit GPR84-agonist stimulated chemotaxis. Inhibition of GPR84-agonist stimulated chemotaxis is useful in the prevention and/or treatment of inflammatory conditions. In particular, the present invention provides methods and assays for identifying agents for use in the prevention and/or treatment of inflammatory conditions (for example inflammatory bowel diseases (IBD), rheumatoid arthritis, vasculitis, lung diseases (e.g. chronic obstructive pulmonary disease (COPD) and lung interstitial diseases (e.g. idiopathic pulmonary fibrosis (IPF)), neuroinflammatory conditions, infectious diseases, autoimmune diseases and/or diseases involving impairment of immune cell functions.