This publication highlights the need for test developers to provide clear explanations of the ability constructs which underpin tests offered in the public domain. An explanation is increasingly required or if the validity of test score interpretation and use are to be supported both logically and with empirical evidence. The book demonstates the application of a comprehensive test validation framework which adopts a socio-cognitive perspective. The framework embraces six core components which reflect the practical nature and quality of an actual testing event. It examines Cambridge ESOL...