The paper takes a critical look at all aspects of fire retardancy, starting with the need for fire safety. The function of a flame retardant is examined and reactive and additive flame retardant classes are contrasted along with their chemical and physical effect mechanisms. Major flame retardant compounds, both halogen and halogen free, are examined in detail. Toxicology and Environmental impact are examined with particular emphasis on Tetrabromobisphenol-A which is the most widely used flame retardant in PCB materials. European legislative directives are also considered.