It appears that there are two distinct practices within public health, namely health promotion and disease prevention, leading to different goals. But does the distinction hold? Can we promote health without preventing disease, and vice versa? The aim of the paper is to answer these questions. First, the central concepts are defined and the logical relations between them are spelt out. A preliminary conclusion is that there is a logical difference between health and disease, which makes health promotion and disease (...) prevention two distinct endeavours. However, since disease is defined in relation to health, as those kinds of internal processes and states that typically lead to ill health, the difference is smaller than it might appear. Second, in order to answer the practical question whether it is possible to promote health without preventing disease, and vice versa, several kinds of public health interventions are discussed. The conclusion is that while health promotion and disease prevention can be distinguished conceptually, they can hardly be distinguished in practice. Most general measures do both at the same time. (shrink)