Using a diverse array of aromatic dimers, we have demonstrated that electrostatic interactions are neither necessary nor sufficient to drive π-stacked systems into parallel-displaced rather than cofacial stacking arrangements. Instead, this ubiquitous behavior is driven by the combination of dispersion and Pauli repulsion, or what we have called the "vdW potential" (E vdW ). The preference for parallel-displaced π-stacking may be enhanced or opposed by electrostatic interactions but emerges nonetheless.