Given the diversity of understanding and interpretation of quality evident in the different traditions discussed above, defining quality and developing approaches to monitoring and improving it requires dialogue designed to achieve: broad agreement about the aims and objectives of education; a framework for the analysis of quality that enables its various dimensions to be specified; an approach to measurement that enables the important variables to be identified and assessed; a framework for improvement that comprehensively covers the interrelated components of the education system and allows opportunities for change and reform to be identified. As earlier sections of this chapter have indicated, cognitive development and the accumulation of particular values, attitudes and skills are important objectives of education systems in most societies. Their content may differ but their broad structure is similar throughout the world. This may suggest that in one sense the key to improving the quality of education – to helping education systems better achieve these objectives – could be equally universal. Considerable research has been directed towards this question in recent years. As Chapter 2 shows, however, the number of factors that can affect educational outcomes is so vast that straightforward relationships between the conditions of education and its products are not easy to determine. Nevertheless, it helps to begin by thinking about the main elements of education systems and how they interact. To this end, we might characterize the central dimensions influencing the core processes of teaching and learning as follows: learner characteristics dimension; contextual dimension; enabling inputs dimension; teaching and learning dimension. outcomes dimension. Figure 1.1 illustrates these dimensions and their relationships, and the following subsections discuss their characteristics and interactions.