The equiatomic CeXX′ phases (X and X′ = elements of the 3 rd , 4 th , or 5 th main group) extend the large series of CeTX intermetallics (T = electron-rich transition metal). These phases crystallize with simple structure types, i.e. ZrNiAl, TiNiSi, CeScSi, α-ThSi 2 , AlB 2 , and GdSi 2 . In contrast to the CeTX intermetallics one observes pronounced solid solutions for the CeXX′ phases. The main influence on the magnetic ground states results from the absence of d electrons. All known CeXX′ phases show exclusively trivalent cerium and antiferro-or ferromagnetic ordering at low temperatures. The crystal chemical details and some structure-property relationships are reviewed.