Abstract: A flame management system comprises two flame detector units which are arranged to view different regions of at least one flame and are connected to separate channels of a processor. Each detector unit has at least two operating modes, such as an infra-red and an ultra-violet operating mode, or a normal and a sensitive infra-red or ultra-violet mode, etc. and is switchable between those modes by the processor. The processor thus selectively processes the output of the two units and actively controls the operating mode of each to obtain responses appropriate to the type and/or condition of the or each flame being monitored. In order to enable both IR and UV monitoring from a single detector unit, the detector includes at least one photo-sensitive member together with an optical element such as an IR filter which operates selectively to deliver an undivided IR or an undivided UV compact to the at least one photo-sensitive member.