High resolution and speed are accomplished in liquid chromatography with long columns, packed with small particles, and operated at high fluid velocities, which demands high inlet pressures. The available pressure drop is best exploited by using columns with low reduced plate heights in the practical velocity range and with packing that withstands high pressures without structural changes. Pellicular sorbents, consisting of uniform porous spherical shells supported by fluid-impermeable, mechanically strong particles, such as glass microspheres, meet these requirements as opposed to many conventional column packing materials. Their advantages are discussed from a theoretical and practical point of view and procedures are outlined for their preparation.