to the cardiopulmonary exercise test, and one which has already been shown to provide useful value in the context of interventional assessment in chronic lung disease. In the following four chapters, the emphasis moves on to the testing of two particular populations: patients with lung disease (both children and adult) and heart disease. Central to the interpretation of exercise test results is the availability of robust sets of normative or reference values. Considerations of exercise testing in prognostic evaluation and in the assessment of responses to interventions (e.g. exercise training, supplemental oxygen and drug therapies) provide a further addition to the previous Monograph. In the final chapter, the indications for exercise testing in clinical practice are discussed, along with proposals for new directions in the development and application of clinical exercise testing. ix