Trace elements are widely used to identify the sources of airborne pollutants and to apportion their contributions to the ambient aerosol through receptor models. Due to the impending loss of Pb and Br as automotive emissions tracers and our inability to distinguish among certain types of emissions using tracer elements, there is a need to identify alternative emissions tracers. Organic compounds may also be useful tracers for sources of particles or toxic air pollutants which do not emit trace metals. Published data on the organic composition of source emissions were reviewed to determine their usefulness for these purposes. Factors affecting the variability of reported organic emissions source profiles have been discussed in detail in this review. The existing data indicate that it may be possible to use polycyclic aromatic hydrocarbons, alkanes and certain apparently unique organic compounds to assist in distinguishing among emissions from certain particulate pollutant sources. These compounds can probably best be used to advantage in combination with trace elemental data. The existing data, however, are not adequate for use in receptor modeling and it will be necessary to simultaneously determine the organic and inorganic composition of emissions from major source types using sampling and analytical methods appropriate to the purpose of receptor modeling.