In order to get some information about the band structure of conduction electrons or holes it is often desirable to measure the magnetoresistance effect. This note describes a practical method for the determination of the three components of the magnetoresistance tensor for crystals having the point group symmetry Oh or 0 . The methods, which depend upon equations (IIIa), (IIIb) or (IIc) in this note, are most convenient for crystals having a cleavage plane (100), (110) or (111) . In this case, all the tensor components can be obtained by means of a single experimental run.