On pp. 18-19 we outlined what we are undertaking as the intellectual and practical aim of this book-the generation of knowledge in the rapidly changing educational world of the 1990s that will be as useful as was the knowledge formerly generated by the International School Effectiveness Research Project in the 1980s. We also outlined how we will look widely into numerous areas and paradigms-school effectiveness, school improvement, educational evaluation-in our search for the 'really useful knowledge' that we need to address our themes.
This chapter begins our task by looking at the ways in which different educational groups have conceptualised and measured the goals of education. Indeed, all researchers in the field of educational effectiveness and all practitioners involved in school improvement face the problem of deciding on their criteria for educational effectiveness and educational improvement. Any discussion about the effectiveness and improvement of education implies an idea about what is 'effective' and what is 'improvement'. In such discussions quite often not only the terms 'effectiveness' or 'improvement' are used, but participants talk about the 'quality' of education of a class or of a school. The term 'quality' is rather vague because it can include almost anything, such as effectiveness, efficiency, and statements about the content, processes, and inputs of education. That is the reason why we prefer the term 'effectiveness' (Creemers, 1994), which refers to means-ends relationships between educational processes and student outcomes.
When we use the term 'quality' later in the text we use it in a restricted sense, and we refer to the effectiveness of education and to