Topics with new or revised events include Immune system (TLR4 cascade, MyD88:Mal cascade on plasma membrane, and MyD88-independent cascade), Cell Cycle (Condensation of prometaphase chromosomes, Mitotic prophase: MASTL facilitates mitotic progression, and Resolution of sister chromatid cohesion), Extracellular matrix organization (Collagen degradation, Elastic fibre formation, and Assembly of collagen fibrils and other multimeric structures), Metabolism (Inositol Phosphate Metabolism, Arachidonic acid metabolism, Mitochondrial Iron-Sulfur Cluster Biogenesis, and Phosphate bond hydrolysis by NUDT proteins), Signal Transduction (Signaling by Activin and Signaling by IGF1R), and Gene expression. New pathway illustrations for this release include Cell Cycle and Apoptosis. R Lill is our external author. A Burgess, YG Chen, KA Fitzgerald, F Granucci, M Holzenberger, R Ito, S Kalamajski, V Malhotra, V Mochida, L Muiznieks, J Napetschnig, S Raleigh, F Rauscher, S Ricard-Blum, TA Rouault, M Rush, T Sorsa, WH Tong, T Wundenberg, I Zanoni, and N Zhang are our external reviewers. Reactome’s SBML export (available here) has been upgraded to Level2 Version4. Our SOAP and RESTful web services, have been moved to a new server. A new series of webinars, which will introduce the Reactome website and our suite of pathway and network visualization and analysis tools, will restart in January 2013. Registration details can be found on EventBrite. A new paper, describing the extension of the Reactome data model and enhancing the web tools to permit the annotation and visualization of protein variants, anti-cancer therapeutics, and other disease processes using Reactome, was published in Cancers.