Qualifications provide evidence of students' achievements against subject content in a specification, giving students the confidence that the skills, knowledge and understanding that they will have acquired during the course of their study provides a strong foundation for further academic and vocational study, and for employment. United Kingdom (UK) qualifications encompass both subject content that must be taught and assessments aligned to that subject matter. GCSE (General Certificate of Secondary Education) Mathematics was introduced in summer 1988. Pearson offers these qualifications as one of five Awarding Organisations (AOs), operating under the regulation of the UK Office of Qualifications and Examinations Regulation. AOs design, develop, deliver, and award the recognition of learning outcomes (knowledge, skills, and/ or competencies) of an individual following an assessment and quality assurance process that is valued by employers, learners, or stakeholders. This efficacy report includes information about the research that informed the qualification's design and summarises all the relevant technical reports associated with the assessment component of the qualification and any impact evaluation research related to the impact the qualification has on learner outcomes.