Erratum: In the article “Brain Control of Movement Execution Onset Using Local Field Potentials in Posterior Parietal Cortex” by Eun Jung Hwang and Richard A. Andersen, which appeared on pages 14363–14370 of the November 11, 2009 issue, the name of the institution with which the authors are affiliated was named incorrectly. It should be “California Institute of Technology,” not “California Institute of Biology.”