  Quantum engineering now allows to design and construct multi-qubit states in
a range of physical systems. These states are typically quite complex in
nature, with disparate, but relevant properties that include both single and
multi-qubit coherences and even entanglement. All these properties can be
assessed by reconstructing the density matrix of those states - but the large
parameter space can mean physical insight of the nature of those states and
their coherence can be hard to achieve. Here we explore how the Wigner function
of a multipartite system and its visualization provides rich information on the
nature of the state, not only at illustrative level but also at the
quantitative level. We test our tools in a photonic architecture making use of
the multiple degrees of freedom of two photons.
