Interleukin-1 (IL-1) plays a crucial role in the development of the pathophysiological responses to infection and inflammation. However, the relative contributions of IL-1 alpha and IL-1 beta remain to be clarified. IL-1 beta-deficient mice are a powerful tool to investigate the specific role of IL-1 beta in various experimental conditions. In this report, we summarize the response of IL-1 beta deficient mice to two different inflammatory stimuli, turpentine and endotoxin. Although IL-1 beta-deficient mice respond normally to the systemic administration of lipopolysaccharide (LPS), they do not develop an acute-phase response in the localized tissue damage model of turpentine injection. The results obtained using the IL-1 beta-deficient mice are compared here with those observed in the IL-1 beta-converting enzyme-deficient, IL-6-deficient, tumour necrosis factor-receptor p55-deficient, and interferon-gamma-receptor-deficient mice.