Evaluation has become increasingly important in educational practice, with significant policy and research interest in recent years. As new learning technologies emerge, there is a need to evaluate how they support diverse student populations. Evaluation is not a simple practice but has evolved to meet the needs of various groups. It involves both describing and judging in terms of merit and worth. The relationship between evaluation and research remains contested, with evaluation contributing to research and providing feedback for teaching and learning practices. However, the use of findings differs: evaluations are used for local decision-making, while research contributes to knowledge. Evaluation is value-driven, with 'merit' referring to intrinsic qualities and 'worth' to extrinsic or contextual value. These concepts are socially constructed, making evaluation a political process. Evaluators may not be objective, as studies can be used to control processes or make the world work more effectively. Evaluation can be reframed to focus on helping people see values rather than making judgments. Approaches to evaluation range from positivist to interpretivist, with a shift from objective data collection to constructivist methods. The rise of new approaches has not led to the abandonment of old ones, and controversies over methods and meanings remain unresolved. Experimental methods compare conditions to demonstrate improvement, but they face ethical and contextual challenges. Illuminative evaluation uses ethnographic strategies to explore contexts and practices. Systems approaches focus on learning outcomes and feedback, while goal-free evaluation focuses on unanticipated outcomes. Action research involves collaboration with participants and iterative cycles of planning, acting, observing, and reflecting. Responsive and utilisation-focused evaluation schools tailor evaluations to stakeholders' needs, prioritising usefulness over rigour. Integrative evaluation models place audience needs above methodology, while evidence-based practice is influenced by medical models, prioritising randomised control trials. Ethical issues in evaluation include informed consent, privacy, and the Hawthorne effect. Evaluators must navigate complex tensions between research and practice, ensuring that findings are used to inform action. The role of the evaluator varies depending on methodology, requiring skills in communication and collaboration. Context influences evaluation, with stakeholders' concerns shaping the process. Evaluation is a political activity, with the potential to support or challenge agendas. The complexity of evaluation highlights the need for clear assumptions and theoretical commitments, as well as ongoing research into its significance and impact.Evaluation has become increasingly important in educational practice, with significant policy and research interest in recent years. As new learning technologies emerge, there is a need to evaluate how they support diverse student populations. Evaluation is not a simple practice but has evolved to meet the needs of various groups. It involves both describing and judging in terms of merit and worth. The relationship between evaluation and research remains contested, with evaluation contributing to research and providing feedback for teaching and learning practices. However, the use of findings differs: evaluations are used for local decision-making, while research contributes to knowledge. Evaluation is value-driven, with 'merit' referring to intrinsic qualities and 'worth' to extrinsic or contextual value. These concepts are socially constructed, making evaluation a political process. Evaluators may not be objective, as studies can be used to control processes or make the world work more effectively. Evaluation can be reframed to focus on helping people see values rather than making judgments. Approaches to evaluation range from positivist to interpretivist, with a shift from objective data collection to constructivist methods. The rise of new approaches has not led to the abandonment of old ones, and controversies over methods and meanings remain unresolved. Experimental methods compare conditions to demonstrate improvement, but they face ethical and contextual challenges. Illuminative evaluation uses ethnographic strategies to explore contexts and practices. Systems approaches focus on learning outcomes and feedback, while goal-free evaluation focuses on unanticipated outcomes. Action research involves collaboration with participants and iterative cycles of planning, acting, observing, and reflecting. Responsive and utilisation-focused evaluation schools tailor evaluations to stakeholders' needs, prioritising usefulness over rigour. Integrative evaluation models place audience needs above methodology, while evidence-based practice is influenced by medical models, prioritising randomised control trials. Ethical issues in evaluation include informed consent, privacy, and the Hawthorne effect. Evaluators must navigate complex tensions between research and practice, ensuring that findings are used to inform action. The role of the evaluator varies depending on methodology, requiring skills in communication and collaboration. Context influences evaluation, with stakeholders' concerns shaping the process. Evaluation is a political activity, with the potential to support or challenge agendas. The complexity of evaluation highlights the need for clear assumptions and theoretical commitments, as well as ongoing research into its significance and impact.