Since coal-fired power plants produce approximately 50% of U.S. energy, the toxic and environmental damaging effects of this energy source are important. Trace metals are emitted in both the gas phase as well as particulates, referred to as coal fly ash, during the incineration of coal. The sources, health and environmental effects, and fate and transport are discussed to lay the foundation of importance of trace metals in the atmosphere. Quantitative measurements from various worldwide studies are discussed, which use the following instrumentations: AAS (atomic absorption spectrometry), ICP-MS (inductively couple plasma mass spectrometry), INAA (instrumental neutron activation analysis), and aerosol TOF-MS (time-of-flight mass spectrometry). The partitioning of the trace metals during combustion as well as post-combustion and gas phase and particulate interactions are explored as well as possible future laboratory experiments to further develop the field of trace metal emission coal combustion.