This thesis establishes a number of connections between foundational issuesin quantum theory, and some quantum information applications. It starts with areview of quantum contextuality and non-locality, multipartite entanglementcharacterisation, and of a few quantum information protocols. Quantum non-locality and contextuality are shown to be essential fordifferent implementations of quantum information protocols known as quantumrandom access codes and quantum communication complexity protocols. I derivesufficient experimental conditions for tests of these quantum properties. I also discuss how the distribution of quantum information through quantumcloning processes can be useful in quantum computing. Regarding entanglementcharacterisation, some results are obtained relating two problems, that ofadditivity of the relative entropy of entanglement, and that of identifyingdifferent types of tripartite entanglement in the asymptotic regime ofmanipulations of many copies of a given state. The thesis ends with a description of an information processing task in whicha single qubit substitutes for an arbitrarily large amount of classicalcommunication. This result is interpreted in different ways: as a gap betweenquantum and classical computation space complexity; as a bound on the amount ofclassical communication necessary to simulate entanglement; and as a basicresult on hidden-variable theories for quantum mechanics. I also show that theadvantage of quantum over classical communication can be established in afeasible experiment.
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