The most widely used media for information storage are magnetic tapes and disks which are manufactured by applying a slurry of magnetic particles as a thin film coating on a substrate. Disk- shaped particles of barium ferrite hold out the promise of greatly increased bit density through the emerging technology of perpendicular recording (where the magnetic dipole is oriented normal to instead of parallel to the surface of the disk or tape). Besides increased bit density, barium ferrite recording media have improved resistance to wear and corrosion. Despite considerable commercial interest, development of barium ferrtie media has been hampered by the difficulty of preventing agglomeration. The inital rates of flocculation will be measured using small-angle laser scattering to monitor the extent of flocculation as a function of time.