Antibodies were raised in laying hens and isolated from the yolk of their eggs by precipitation with precooled (-20 degrees C) propane-2-ol and removing lipid material with propane-2-ol and acetone. The dried precipitate was extracted with phosphate buffer and shown to contain IgG antibodies and a small amount of additional protein. By Ouchterlony gel diffusion and rocket immunoelectrophoresis, the concentration and quality of specific antibodies in the extracts were comparable to those found in the serum of rabbits or to the IgG separated from yolk by other methods. The new isolation procedure is rapid, reliable and convenient.