The ICILS assessment framework articulates the basic structure of the study, providing a description of the field and the constructs to be measured. This book outlines the design and content of the measurement instruments, sets down the rationale for those designs, and describes how measures generated by those instruments relate to the constructs. Hypothesized relations between constructs provide the foundation for some of the analyses that follow. Above all, the framework links ICILS to other similar research, enabling the contents of this assessment framework to combine theory and practice in an explication of both the ‘what’ and the ‘how’ of ICILS.