Although a quarter of the energy density of the Universe is comprised of dark matter, its true nature remains a mystery. Weakly Interacting Massive Particles (WIMPs) have provided the standard theory paradigm to date, but the lack of detection has motivated the community to rethink the allowed possibilities.
A broad class of dark sector models exist, providing an exciting and well-motivated alter- native. In such scenarios, the dark matter resides in a hidden sector that communicates with the Standard Model via a suppressed portal coupling. Non-trivial dynamics in the hidden sector can lead to novel phenomenology, whose thorough characterization has only begun. The goal of this workshop is to further the development of a full-fledged experimental and observational program for dark sectors, akin to what has been in place for the standard WIMP. We plan to explore terrestrial probes such as collider, beam-dump and direct detec- tion experiments, as well as astrophysical and cosmological signatures.