Over the last few years the intricate interaction between immune system and adipose tissue has been recognized. Indeed, it has been suggested that adipose tissue is not only a mere site of lipid and energy storage but can be considered as an "immune-related" organ producing a series of molecules named adipokines. Among these, leptin, an adipocyte-derived cytokine-like hormone, seems to play a pivotal role in the regulation of several neuroendocrine and immune functions. In this review, we describe the effects of leptin in inflammation and immunity, and speculate on the possible modulation of the leptin axis in novel adipopharmacotherapeutic settings.Biomedical Reviews 2006; 17: 53-62.