  We expose the information flow capabilities of pure bipartite entanglement as
a theorem -- which embodies the exact statement on the `seemingly acausal flow
of information' in protocols such as teleportation. We use this theorem to
re-design and analyze known protocols (e.g. logic gate teleportation and
entanglement swapping) and show how to produce some new ones (e.g. parallel
composition of logic gates). We also show how our results extend to the
multipartite case and how they indicate that entanglement can be measured in
terms of `information flow capabilities'. Ultimately, we propose a scheme for
automated design of protocols involving measurements, local unitary
transformations and classical communication.
