Magnetic fields are an important constituent in the interstellar medium, but unlike gas, dust, and cosmic rays, they do not radiate, and consequently cannot be observed directly.  Instead, observers identify signatures of the field in an effort to piece together its topology.  Determining the structure of the magnetic field within our Galaxy (and others) provides necessary constraints for models  attempting to understand how the field originally formed and how it is evolving. Some of the greatest advancements in this area of study have come from observations from a radio telescope located in the hills near Penticton, British Columbia (at the Dominion Radio Astrophysical Observatory).  In this talk, I will review the current  status of what is known (or perhaps, what we think we know), what remains highly contentious, and how Canada is shaping the future studies of cosmic magnetism.