The major issues and tradeoffs surrounding phosphor selection for field-emission flat panel displays are identified. The two main classes of commercially available phosphors applicable to flat panel displays are contrasted, and the major physical, electrical, chemical and optical factors effecting phosphor selection are discussed. The implications of screen layering designs and cathode materials are described as they relate to phosphor characteristics. Resolution requirements for displays severely limits the maximum anode voltage, which in turn forces specific phosphor choices. Possible solutions to these limitations are explored.