Based on the synthesis and characterization of a series of new (poly‐)selenide salts, a classification of anionic (poly‐)selenide‐containing compounds is proposed. The new compounds were categorized according to these classes. Synthetic approaches of organic cation‐stabilized (poly‐)selenide compounds that have been already known from literature are reviewed, along with the crystal structures of new compounds and some spectroscopic data, and an experimental and theoretical approach towards dichroism observed in some of the triselenides.