NERS-active structures for use in Raman spectroscopy include protrusions extending from a surface of a substrate. A Raman signal-enhancing material is disposed on at least one surface of a first protrusion and at least one surface of a second protrusion. The Raman signal-enhancing material disposed on the first protrusion projects laterally in a direction generally towards the second protrusion, and the Raman signal-enhancing material disposed on the second protrusion projects laterally in a direction generally towards the first protrusion. At least a portion of the Raman signal-enhancing projecting from the first protrusion and at least a portion of the Raman signal-enhancing material projecting from the second protrusion may be separated by a distance of less than about 10 nanometers. Raman spectroscopy systems include such NERS-active structures, and methods for performing Raman spectroscopy include irradiating an analyte proximate such a NERS-active structure and detecting Raman-scattered radiation scattered by the analyte.