According to him:

- "we should assemble evidence of success using a kind of 'judicial principle' - by which I mean providing evidence which would lead to a jury committing themselves to action even when 100% proof is not available." (Tones, 1997)

- This approach has several advantages: (1) it is a concept of "evidence" which most people can understand; (2) It provides scope for considering a broad range of sources and types of evidence, which is essential in health promotion

- However, it does not in and of itself give us any guidance regarding how evidence should be collected, shared or used, which are the remaining challenges that I would like to address.