Multiple Databases

Is it possible to create a new WP site and have it import information from a second database hosted elsewhere? My client currently uses another developer who has an extensive database that holds information collected from several other branches and needs to use that information to propagate the site as it’s changed but hates the interface on their site. So they have hired my company to make a “pretty” site but need the other information as well.

They want the information on the other database to load member lists, events, forums etc.. that are added to by other branches using the other database.

I hope this makes sense. Ideally I would like to re-do the entire database but they do not see this as a possibility as they run several things from it aside from the site.