Most fatalities from fires are not due to burns, but are a result of inhalation of toxic gases produced during combustion. Fire produces a complex toxic environment involving flame, heat, oxygen depletion, smoke and toxic gases. As a wide variety of synthetic materials is used in buildings (insulation, furniture, carpeting, and decorative items) the potential for severe health impacts from inhalation of products of combustion during building fires is continuously increasing. In forest fires the burning of biomass leads to smoke emissions, the composition of which, as well as the relative health impacts from their inhalation, depends on the ecosystem's chemical and physical features and the local environmental parameters. In the present review, health problems that appear to people exposed to fire smoke and especially to firefighters are described and suggestions for fire management and prevention are made.