The selection of filtration media by the automotive design engineer is dependent upon many factors. The most obvious being material compatibility, efficiency, flow rate, dirt holding capacity and others. Not quite as obvious, but until recently, of less concern has been the issue of extended life and reusable media. Discussion will briefly highlight these requirements and considerations in addition to the reasons for their importance as well as overall filtration media trends.Also offered is an overview of the most common filtration media and many of their automotive end-use filtration applications. Special emphasis will be placed on a number of emerging materials and new media expected to play a role and have a notable impact in the industry over the next several years. Examples for use in both air and liquid include; activated carbon, asymmetric porous plastic, fluoro-polymer meltblown nonwoven, sheath/core wire cloth, monofilament fabrics and netting, sintered polyimide and stainless steel fiber fabrics, triboelectric media, low cost membranes and other unique materials and constructions.