We propose a theory which accounts for the linear magnetoresistance found in the transverse and longitudinal components in various metals. The theory is based on the existence of quasiperiodic static fluctuations, which have the anisotropy of the lattice and may be due to electron-phonon and/or electron-electron interactions. The fluctuations produce no noticeable change in the static properties of the metal but produce the dominant linear increase of the resistance at high magnetic fields.