Abstract: A polarization-preserving single mode fiber coupler, fabricated by a method which does not require mutually aligning the fiber polarization axes provided the actual misalignment angle is not close to 90.degree.. The protective jackets from two or more polarization-preserving single mode birefringent fibers are partially removed and the fibers are twisted around each other to bring them into contact over the jacketless region and provide a coupling length that is large compared to the birefringent beat length of the fibers. Next, the cladding layers of the fibers in the contacting region are partially etched without degrading the birefringent beat length over their coupling length. Then, the etched region is heated to the softening point of the fibers while axial tension is applied to taper and fuse the etched region until a desired coupling of the fibers is achieved. Finally, a mechanical supporting structure is added to the tapered and fused region of the fibers.