Dynamics of Coupled Structures, Volume 4: Proceedings of the 36th IMAC, A Conference and Exposition on Structural Dynamics, 2018, the fourth volume of nine from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of the Dynamics of Coupled Structures, including papers on: Experimental Nonlinear Dynamics; Joints, Friction & Damping; Nonlinear Substructuring; Transfer Path Analysis and Source Characterization; Analytical Substructuring & Numerical Reduction Techniques; Real Time Substructuring; Assembling & Decoupling Substructures & Boundary Conditions.