A new approach to fitting powder patterns via nonlinear least-squares analysis is described. This fitting method is designed to be particularly sensitive to the frequencies of important features and insensitive to discrepancies in intensity between calculated and observed spectra. A description of an optimized powder pattern calculation routine is given with a discussion of the calculation of chemical-shift, dipole-coupled chemical-shift, and nonaxially symmetric quadrupolar powder spectra. Examples of fits of chemical-shift and dipole-coupled chemical-shift powder patterns are shown. The potential applications and limitations of the technique are discussed. © 1988.