The first part of the chapter is dedicated to magnetic properties of metal phosphides and arsenides, mainly those with MX and M
2
X formulas. Their crystal structures are classified on the basis of the relative M–M and M–X bonding strength. Electronic origin instabilities of the d‐magnetism are underlined with reference to magnetoelastic, magnetic field, and pressure induced transitions, thus revealing high‐performing materials in terms of colossal magnetocaloric properties. In short, the second part reports on the knowledge of magnetic chalcogenides, from zinc‐blende spintronic materials up to recent studies on rare‐earth and uranium magnetic compounds.