This document is a mark scheme for the January 2013 A-level Mathematics exam. It provides guidance for examiners on how to mark students' responses consistently. The mark scheme was developed by the Principal Examiner and a panel of teachers, and was refined through a standardization process where examiners analyzed sample scripts. The mark scheme is a working document that may be expanded based on students' actual responses. Details of the mark scheme can change between exam sittings depending on the specific questions asked.