The next generation of X‐ray monitoring missions should include detectors sensitive to X‐rays with energies below 2 keV. This capability will allow us to explore the physics associated with soft sources, including hot white dwarfs, intermediate‐mass black holes, soft active galactic nuclei, soft emission in &ggr;‐ray burst afterglows, and many X‐ray active stars. I also show, usingChandradata from 4 galaxies, that more than half of the photons from even so‐called “canonical” X‐ray sources (with strong emission signatures above 2 keV) have energies below 2 keV. This suggests that soft‐X‐ray monitoring can open new doors to our understanding of even well‐studied sources. © 2004 American Institute of Physics