With their unique ability to concentrate and scatter light, plasmonic nanomaterials have been the focus of tremendous synthesis and characterization efforts in the past two decades. Recently, the topic of reversibly reconfigurable plasmonic nanomaterials has become an intensive research area offering the opportunity to reconfigure the optical, mechanical, electronic, and catalytic properties of materials with promising applications in fields ranging from biosensors to nanorobotics and energy. This Perspective discusses the state of the art in the fabrication and application of reversibly reconfigurable colloidal plasmonic nanomaterials based on the actuation of interparticle couplings and explores some promising directions for future research ranging from direction control, two-dimensional materials, and the incorporation of feedback mechanisms for designing robust responses.