There is a great deal of interest in the relationship between the immune system and in particular inflammation and psychiatric syndromes. This presentation focuses on the relationship between inflammation and mood disorders. The goals of the talk are; (1) to distinguish between acute and chronic inflammatory states, (2) discuss the impact of peripheral inflammation on dopamine and glutamate systems of some people with inflammation and major depressive disorder, (3) review a series of studies we have performed exploring inflammation, depression and the resolution of both inflammation and depression with a high dose omega-3 fatty acids.