Metabolic and immune systems are the most fundamental requirements for survival, and many metabolic and immune response pathways or nutrient- and pathogen-sensing systems have been evolutionarily highly conserved. Consequently, metabolic and immune pathways are also highly integrated and interdependent. In the past decade, it became apparent that this interface plays a critical role in the pathogenesis of chronic metabolic diseases, particularly obesity and type 2 diabetes. Importantly, the inflammatory component in obesity and diabetes is now firmly established with the discovery of causal links between inflammatory mediators, such as tumor necrosis factor (TNF)-α and insulin receptor signaling and the elucidation of the underlying molecular mechanisms, such as c-Jun NH₂-terminal kinase (JNK)- and inhibitor of nuclear factor-κB kinase–mediated transcriptional and posttranslational modifications that inhibit insulin action. More recently, obesity-induced endoplasmic reticulum stress has been demonstrated to underlie the initiation of obesity-induced JNK activation, inflammatory responses, and generation of peripheral insulin resistance. This article will review the link between stress, inflammation, and metabolic disease, particularly type 2 diabetes, and discuss the mechanistic and therapeutic opportunities that emerge from this platform by focusing on JNK and endoplasmic reticulum stress responses.