Mindbridge by Joe Haldeman
Jacque LeFavre is a tamer - a member of one of the tough and honed exploration teams that, since the dramatic discovery of the Levant-Meyer Translation, humankind has been able to send to the stars. And Jacque's first world is the second planet out from Groombridge 1618. It isn't an especially promising place; the planets accompanying small stars rarely pan out. But the strange and mysterious creature that Jacque and his colleagues find there, with its gift of telepathy, leads to contact with the alien and enigmatic L'vrai, and confronts humankind with an awesome opportunity - and appalling danger.