  In the large family of two-dimensional (2D) layered materials including
graphene, its honeycomb analogs, and transition-metal dichalcogenides, the
interlayer coupling plays a rather intriguing role. On the one hand, the weak
van der Waals interaction that holds the layers together endows these compounds
with quasi-2D properties, which might imply small interlayer effects on the
electronically active bands. On the other hand, the oft-witnessed differences
in electronic, optical, and magnetic behaviors of monolayers, bilayers, and
multilayers of the same compound must have as their microscopic origin the
detailed interlayer hopping parameters. Given the few experimental reports that
have attempted to explicitly extract these parameters, we employ soft-x-ray
angle-resolved photoemission spectroscopy (SX-ARPES) to probe the interlayer
coupling in superconducting 2$H$-NbS$_2$. We visualize the S 3$p_z$ bands that
disperse with respect to the out-of-plane momentum and introduce a simple
tight-binding model to extract the interlayer hopping parameters. From
first-principles calculations, we clarify how atomic distances and the proper
accounting for screening via hybrid functionals influence these bands. The
knowledge of interlayer hopping parameters is particularly pertinent in
NbS$_2$, where recent experiments have uncovered fingerprints of
finite-momentum superconductivity in the bulk material and heterostructures.
