Monocyte chemoattractant protein-1 (MCP-1) is a potent chemoattractant for monocytes and macrophages to areas of inflammation. MCP-1 is a prototypical chemokine subject to coordinated regulation by immunomodulatory agents. Since MCP-1 is implicated in multiple inflammatory diseases, it is a potential target for the treatment of these disorders. In this review, we will provide background information and summarize the MCP-1 structure and signaling pathways. Its involvement in multiple diseases, such as tumour development, atherogenesis and rare autoimmune diseases is also revised.