Last time I visited the Ethnologue website, they placed the number of active languages in the world at just over 7000. Unsurprisingly, it's a damn tricky number to nail down and is certainly controversial.

Anywho, some linguists project that by the end of this century, the number of active languages will be about 300. Living in the age we do, though, the roughly 6700 languages that may disappear from use will be quite well documented. Anyone who takes it upon him or herself to learn or study any of these languages will be able to do so.

I think this probably represents the best we can do. Some processes simply transcend management, and I'd certainly put the interaction of cultures into that group. That which falls out of active use becomes the purview of academia.

Edit: I should probably have said the languages *may* be well documented. The are still some that have no written counterpart, and those could be problematic. Others may simply escape adequate documentation.