This page examines the ways in which apes have demonstrated communication skills, and the research behind it. Edit
"Kanzi and Lucy" - in this audio story from RadioLab, the producers ask: "Just how close can we get to our closest primate relatives? That's the question at the heart of our show Lucy -- a question that we try to answer by getting to know a chimp named Lucy, and a bonobo named Kanzi." http://www.radiolab.org/story/lucy-and-kanzi/
Koko - This is perhaps the most famous case of human-ape communication. This story documents the incredible development of a gorilla named Koko, whose learning of American Sign Language (and understanding of spoken English) gives new meaning to the ideas of animal intelligence and inter-species communication.
What would an ape sound like if it could actually speak? Some researchers at Princeton think they know.