This contribution reviews applications of NMR spectroscopy in the investigation of the structure and the intra- and intermolecular interactions of purine derivatives. Purines represent a highly important class of heterocyclic compounds that are widely distributed in all living organisms, not only as constituents of nucleic acids, but also as signal molecules. Their structure, electron distribution, and proton-transfer processes determine their chemical reactivity, interactions with solvents, and, subsequently, also their biological activity and function. Along with X-ray diffraction, NMR spectroscopy represents one of the most important experimental tools for investigating molecular topology at the atomic level. In the following text, NMR methods suitable for studying the purine structure and their application to exploring samples at natural levels of the 13C and 15N isotopes are briefly reviewed. As will be shown, isotropic 13C and 15N chemical shifts, 1H-13C one- and three-bond J-coupling constants and 1H-15N one- and two-bond couplings are the commonly used characteristic parameters for NMR in the solution state. In the solid state, CP MAS spectra of powder samples provide the principal values of the chemical-shift tensors. Quantum chemical calculations on the DFT level support and explain the experimental data. Due to the extremely wide scope of the topic, no attempt is made to cover the area completely. Rather, typical examples of applications and recently published contributions in all of the areas identified above are included to provide the reader with a summary of the current efforts to increase our knowledge and understanding of the interactions at the atomic, molecular and intermolecular level in purine and its derivatives.