Active experiments provide a unique opportunity to introduce controlled perturbations into the geospace environment, investigating phenomena that are otherwise difficult to isolate and study through passive observations alone.  Using a broad range of approaches, these experiments give insight into wave-particle interactions, wave propagation, plasma instabilities, artificial structuring, and other physical phenomena that are present in the geospace environment.  Utilizing various approaches gives insight into different interactions, and when combined, can lead to increased understanding of the geospace environment as a whole.  This session aims to promote connections between communities performing active experiments while advancing experimental approaches in the geospace sciences.  We welcome contributions, including but not limited to ionospheric modification experiments, sounding rocket missions, and space-based experiments.  Laboratory experiments that inform or replicate space plasma phenomena are also welcome.