54 ▸ Additional material is published online only. To view these files please visit the journal online (http://dx.doi. org/10.1136/bjsports-2013-092313). To cite: McCrory P, Meeuwisse WH, Aubry M, et al. Br J Sports Med 2013;47:250–258. PREAMBLE This paper is a revision and update of the recommen-dations developed following the 1st (Vienna 2001), 2nd (Prague 2004) and 3rd (Zurich 2008) International Consensus Conferences on Concussion in Sport and is based on the deliberations at the 4th International Conference on Concussion in Sport held in Zurich, November 2012. 1–3 The new 2012 Zurich Consensus statement is designed to build on the principles outlined in the previous documents and to develop further concep-tual understanding of this problem using a formal consensus-based approach. A detailed description of the consensus process is outlined at the end of this document under the Background section. This document is developed primarily for use by physi-cians and healthcare professionals who are involved in the care of injured athletes, whether at the recre-ational, elite or professional level. While agreement exists pertaining to principal messages conveyed within this document, the authors acknowledge that the science of concussion is evolving, and therefore management and return to play (RTP) decisions remain in the realm of clinical judgement on an individualised basis. Readers are encouraged to copy and distribute freely the Zurich Consensus document, the Concussion Recognition Tool (CRT), the Sports Concussion Assessment Tool V.3 (SCAT3) and/or the Child SCAT3 card and none are subject to any restrictions, provided they are not altered in any way or con-verted to a digital format. The authors request that the document and/or the accompanying tools be dis-tributed in their full and complete format. This consensus paper is broken into a number of sections 1. A summary of concussion and its management, with updates from the previous meetings; 2. Background information about the consensus meeting process; 3. A summary of the specific consensus ques-tions discussed at this meeting; 4. The Consensus paper should be read in conjunc-tion with the SCAT3 assessment tool, the Child SCAT3 and the CRT (designed for lay use).