[en] EXAFS is measured at the Nb K-edge in the layered compounds NbS₂, NbSe₂ and in the same materials after intercalation with the first-row transition metals. It is analyzed by a method which combines Fourier transform and curve-fitting techniques. Parameterized phase shift and amplitude functions for describing Nb-S and Nb-Se interactions are obtained from EXAFS spectra of NbS₂ and NbSe₂. Application of these phase shifts and amplitudes to the EXAFS spectra of other compounds yields distance determinations to an accuracy consistently better than 0.003 nm for atoms bound to Nb. The number of coordinating atoms are also determined with a reasonable degree of certainty. (author)