An electroluminescent device comprising: a first charge-carrier injecting layer for injecting positive charge-carriers; a second charge-carrier injecting layer for injecting negative charge-carriers; a layer (3, 5) of a first organic material located between the charge-carrier injecting layers; and a first light-emissive region (5, 7) located between the layer of a first organic material and one of the charge-carrier injecting layers, said first region comprising a light-emissive second organic material having an energy-gap less than that of the first organic material; characterised in that it also comprises a second light-emissive region located between the layer of a first organic material and one of the charge-carrier injecting layers, said second region comprising a blend or mixture of a first component of a light-emissive third organic material having an energy-gap greater than that of the first organic material, and a second component having at least one energy level different in energy from that of the first component; such that when charge-carriers are injected in the first region by the charge-carrier injecting layers light is emitted most from the second organic material and when charge-carriers are injected in the second region by the charge-carrier injecting layers light is emitted most from the third organic material. a first charge-carrier injecting layer for injecting positive charge-carriers; a second charge-carrier injecting layer for injecting negative charge-carriers; a layer (3, 5) of a first organic material located between the charge-carrier injecting layers; and a first light-emissive region (5, 7) located between the layer of a first organic material and one of the charge-carrier injecting layers, said first region comprising a light-emissive second organic material having an energy-gap less than that of the first organic material; characterised in that it also comprises a second light-emissive region located between the layer of a first organic material and one of the charge-carrier injecting layers, said second region comprising a blend or mixture of a first component of a light-emissive third organic material having an energy-gap greater than that of the first organic material, and a second component having at least one energy level different in energy from that of the first component; such that when charge-carriers are injected in the first region by the charge-carrier injecting layers light is emitted most from the second organic material and when charge-carriers are injected in the second region by the charge-carrier injecting layers light is emitted most from the third organic material. a second light-emissive region located between the layer of a first organic material and one of the charge-carrier injecting layers, said second region comprising a blend or mixture of a first component of a light-emissive third organic material having an energy-gap greater than that of the first organic material, and a second component having at least one energy level different in energy from that of the first component; such that when charge-carriers are injected in the first region by the charge-carrier injecting layers light is emitted most from the second organic material and when charge-carriers are injected in the second region by the charge-carrier injecting layers light is emitted most from the third organic material.