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The phosphole system is investigated both theoretically and by uv photoelectron spectroscopy. The theoretical approach confirms that phospholes despite their pyramidal structure are "aromatic" systems. Their "aromatic" stabilization relative to the conjugatively interrupted subunits ds-butadiene and PR is gained from nx* conjugative and P-C/x* hyperconjugative interactions between both subunits. These interactions appear not to be accompanied by appreciable x-charge transfer (i.e., electron delocalization) from the PR unit to the x part mainly due to strong electron acceptance from the phosphorus d orbitals. In addition, the photoelectron spectroscopic results corroborate strong P-C/x hyperconjugative but only weak n/x conjugative mixing. The results of the present study show that the n orbital energy is not a suitable means to deduce the "aromatic" nature of phospholes as a consequence of the combined nx* and nx interactions. Moreover, the results constitute a first indication of the important role played by P-C hyperconjugation in these systems.