It is often said that archaeological sites remain in remarkable condition when situated underwater. Indeed, this is often true. However, there are many natural and anthropogenic processes that threaten this rich archaeological resource. As part of the management options, we can preserve sites in situ, do nothing, excavate and even remove sites from their environment. If we preserve a site in situ, this often means an active approach. Is it worth managing sites in situ? There are many reasons why we should; each of them requiring a different approach relating to the values we attach to underwater archaeological sites.