The structural, electronic, magnetic, and optical properties of AuAl 2, AuGa 2, AuIn 2, and PtGa2 are reviewed. These experimental results are compared with the values of the density of states at the Fermi level derived from band-structure calculations. The so-called “ AuGa 2 dilemma” and the controversial positions of the Au 5d bands in AuAl 2, AuGa 2, and AuIn 2 are discussed. The physical properties of PtGa 2 are summarized and compared with those of the Au intermetallic compounds. Recent researches on the growth and characterization of these compounds in thin-film form are also presented.