Erratum: In the article "Death in the Balance: Alternative Participation of the Caspase-2 and -9 Pathways in Neuronal Death Induced by Nerve Growth Factor Deprivation," by Carol M. Troy, Sylvia A. Rabacchi, Justin B. Hohl, James M. Angelastro, Lloyd A. Greene, and Michael L. Shelanski, which appeared on pages 5007-5016 of the July 15, 2001 issue, a printer's error introduced an incorrect definition for "DIABLO/Smac" in the abstract. The fifth sentence of the abstract should read "The mechanism underlying the shift is the result of a threefold compensatory elevation of caspase-9 expression and a doubling of levels of direct IAP binding protein with low pI (DIABLO)/second mitochondria-derived activator of caspase (Smac), an IAP inhibitor, both at the mRNA and protein levels." Also, the sixteenth sentence of the introduction should read "Recent work has revealed a mammalian inhibitor of IAPs, direct IAP binding protein with low pI (DIABLO)/second mitochondria-derived activator of caspase (Smac), that inhibits the IAPs and thus promotes caspase-9, -3, and -7 activities (Du et al., 2000; Verhagen et al., 2000)." The file has been altered accordingly.