Abstract The 73Ge spectra of some germanium-tetra-halides, germanium-tetra-alkyles, and of germanium-tetra-methoxide have been observed. The chemical shifts of these 73Ge NMR-lines were measured as functions of the temperature in the range up to 50 °C. In CS2-and benzene-solutions of Gel4 , two 73Ge-lines were found. The 73Ge NMR-spectrum of Ge(CH3)4 caused by indirect spin-spin-coupling between the 73Ge nucleus and the protons is well resolved. The spin-spin-coupling constants of Ge(CH3)4 and of Ge(OCH3)4, which shows an unresolved spectrum, were evaluated by an iterative least square fitting routine. The relaxation times T2 (in the range 30...740 msec) measured by the Carr-Purcell spin-echo-technique and calculated from the line widths are in good agreement. Precision measurements of the ratios of the Larmor frequencies of 73Ge in GeCl4, 41K in aqueous KF-solution and 2H in pure heavy water lead to a magnetic moment of 73Ge: μ = -(0.876 78 ± 0.000 01) μN (uncorrected).