Application of ion beam analysis techniques in the studies of material transport and fuel inventory in the controlled fusion devices is exemplified. Enhanced proton scattering on the carbon isotopes 1 2 C(p,p) 1 2 C, 1 3 C(p,p) 1 3 C and secondary ion mass spectrometry allowed for determination of carbon erosion and re-deposition on the wall components following the experiments with a tracer ( 1 3 CH 4 ) injection into the plasma edge at the TEXTOR tokamak. For the assessment of the deuterium fuel accumulation in the plasma facing components depth profiling by means of nuclear reaction analysis, 3 He(d,p) 4 He, was performed. Advantages and limitations of those nuclear methods in solving experimental problems are addressed.