Robots out in the world today work for people but not with people. Before robots can work closely with ordinary people as part of a human-robot team in a home or office setting, robots need the ability to think and act more like people. When people act jointly as part of a team, they engage in collaborative planning, which involves forming a consensus through an exchange of information about goals, capabilities, and partial plans. In this talk, I describe a framework for robots to understand and generate messages broadly — not only through natural language but also by functional actions that carry meaning through the context in which they occur. Careful action selection allows robots to clearly and concisely communicate meaning with human partners in a manner that almost resembles telepathy. I show examples of how this implicit communication can facilitate activities as basic as hallway navigation and as sophisticated as collaborative tool use in assembly tasks. I also show how these abilities can assist in recovery after a failure.