In the article by D. Scheuner and R.J. Kaufman, “The unfolded protein response: a pathway that links insulin demand with β-cell failure and diabetes” (Endocrine Reviews 2008; 29(3):317–333), an error appeared on page 327 of the printed version. In the first column, second paragraph, the fourth sentence should read as follows: “Heterozygous Xbp1-/+ mice fed a high-fat diet develop insulin resistance in liver and adipose tissue due to JNK activation and inactivating phosphorylation of IRS-1 and IRS-2.” The authors apologize for the error.