A combination of two-dimensional (2D) NMR techniques, namely, (H-1-H-1) NOESY, and ROESY, has been used for the first time to study cross-relaxation and exchange phenomena in a poly(acrylamide) hydrogel. Intramolecular cross-relaxation interactions are detected for the main-chain protons and are seen to arise from polymer mobility occurring in the long correlation regime (omega(0) tau(c) much greater than 1). Temperature-dependent studies show chemical exchange, direct and relayed cross-relaxation pathways for the magnetization transfer. For amide protons, cross relaxation dominates over chemical exchange at room temperature and below. Intermolecular exchange and cross-relaxation processes are identified for hydrated water, and evidence has been gathered for interacting water molecules with a relatively long reorientational correlation time. The 2D data also point to the most probable location of water close to the carbonyl group.