Neutron scattering is a powerful tool for the analysis of structure and dynamics in organic semiconductor systems, including conjugated polymers. This chapter covers the major techniques that have been applied to study phase behaviour, structure and dynamics in these systems. Elastic scattering techniques, including small-angle neutron scattering, neutron reflectometry and grazing incidence small-angle neutron scattering serve as advanced and complementary tools to non-destructively probe structure over nanometre length scales. Quasi-elastic neutron scattering is also briefly discussed to demonstrate its value in the analysis of dynamic motion in conductive polymers. An introduction to the basic principles, theories and data analysis are provided for each technique, in addition to example applications from the literature.