Internal sizing usually consists of rosin milk added to the fibre furnish just before it goes onto the paper machine, and is precipitated onto the fibres with papermaker's alum. The purpose of such hardsizing is to reduce the wettability of the sheet, although it may actually enhance its receptivity to oil-based inks. Surface sizing usually consists of special starches added to the formed sheet near the dry end of the paper machine. Animal glue or mixtures of glue and starch may also be used. Surface sizing seals down surface fibres, decreases oil receptivity, and adds stiffness and rattle to a sheet. Sizing in coated papers acts primarily to bond the coating pigment to the base stock. Common coating adhesives are starch, soybean protein, casein and lattices. The sizings appropriate for different types of papers are discussed. -- AATA