Author Omitted. In the article titled “Three Families With Amyotrophic Lateral Sclerosis and Frontotemporal Dementia With Evidence of Linkage to Chromosome 9p” by Valdmanis et al, published in the February issue of the Archives (2007;64:240-245), an author was omitted from the byline and the “Author Affiliations” and “Author Contributions” sections. On page 240, the byline should have read as follows: “Paul N. Valdmanis, BSc; Nicolas Dupre, MD, MSc; Jean-Pierre Bouchard, MD; William Camu, MD; François Salachas, MD; Vincent Meininger, MD; Michael Strong, MD, FRCPC; Guy A. Rouleau, MD, PhD.” On page 245, left-hand column, the “Author Affliliations” section should have read as follows: “Author Affiliations: Center for the Study of Brain Diseases, University of Montreal, Centre Hospitalier de l’Université de Montreal (CHUM) Research Center, Notre-Dame Hospital (Mr Valdmanis and Drs Dupre and Rouleau) and Department of Human Genetics, McGill University (Mr Valdmanis), Montreal, Québec; Department of Neurological Sciences, Centre Hospitalier Affilié Universitaire de Québec (CHAUQ), Hôpital de l’Enfant-Jésus, Québec City, Québec (Drs Dupre and Bouchard); Unité de Neurologie Comportementaleet Dégénérative Molecular Unit, Institute of Biology, and Clinique du Motoneurone, Service d'Explorations Neurologiques, Hôpital Guy de Chauliac, Montpellier, France (Dr Camu); Fédération des Maladies du Système Nerveux, Division Paul Castaigne, Hôpital de la Salpêtrière, Paris, France (Drs Salachas and Meininger); and Department of Clinical Neurological Sciences, University of Western Ontario, London (Dr Strong).” Farther down the same column, the “Author Contributions” section should have read as follows: “Author Contributions:Study concept and design: Valdmanis and Rouleau. Acquisition of data: Valdmanis, Bouchard, Camu, Salachas, Meininger, Strong, and Rouleau. Analysis and interpretation of data: Valdmanis, Dupre, and Rouleau. Drafting of the manuscript: Valdmanis. Critical revision of the manuscript for important intellectual content: Dupre, Bouchard, Camu, Salachas, Meininger, Strong, and Rouleau. Statistical analysis: Valdmanis. Obtained funding: Rouleau. Administrative, technical, and material support: Valdmanis, Dupre, Salachas, Meininger, and Rouleau. Study supervision: Bouchard and Rouleau. Family collection: Camu and Strong.” This article was corrected for error in data on April 24, 2007, prior to publication of the correction in print.