This text is the first component in the "MEI Structured Mathematics" series. It is designed to be both an access course for those who wish to proceed to AS or A-Level, but are not yet ready to do so, and also to be a first mathematics unit with Advanced GNVQs. The content covers the requirements of the Application of Number core skills for advanced GNVQ courses. It applies mathematics in a variety of contexts from industry and medicine to sport and show business, and includes carefully-structured exercises and investigations.