Molecular imaging has had little application to multiple sclerosis thus far. However, advances in preclinical studies and proofs-of-principle provided for other inflammatory disorders highlight the potential for using positron emission tomography, single-photon emission computerized tomography or MRI-based molecular imaging methods to define the distribution and trafficking of specific immune effector cells, or to follow changes in specific molecular neuropathology in multiple sclerosis. If this promise can be realized, novel insights into the dynamics of in vivo multiple sclerosis neuropathology can be expected. Furthermore, powerful new approaches to testing the pharmacology of novel therapeutics will become possible. Molecular imaging could also contribute to 'personalizing' treatments for better outcomes.