The magnetic anisotropy phase diagrams of Pr2Co17-,Fen and Pr2Co17-,Fez-,Ty (T=Mn, Zr, Ti, Hf) compounds have been determined. Two spin reorientation temperatures, TSr1 and Tsr2, have been observed. Near the Ts,l or Ts,2 boundary the anisotropy is conical; between the two spin reorientation temperatures they exhibit uniaxial anisotropy and beyond these limits they are planar. Introduction --0-y...