GNU Octave(1) has been available for nearly two decades. During that time the scope of the project has grown from a simple interface to numerical tools intended for classroom use to a capable system with hundreds of thousands of users worldwide. This paper provides an overview of the Octave project, summarizes some recently completed additions, and describes in detail the ways in which Octave may be used to perform reproducible research. (c) 2012 Elsevier Ltd. All rights reserved.