Belt for drive engineering, composed at least of - a belt structure made of a polymeric material with elastic properties, encompassing an outer layer as belt backing and a substructure with a force-transmission zone ; and - a tension-member system embedded in the belt structure; characterized in that the belt structure is composed of at least two different materials A and B, namely of: - a first material A which comprises a fire-retardant additive and which has been incorporated in the belt structure wherever there is no requirement for the high level of mechanical properties; where the quantitative proportion of the fire-retardant additive is from 5 to 50% by weight; and - a second material B which has low, or no, content of a fire-retardant additive and which is used in the belt-structure region which is subject to the highest level of mechanical requirements, where the quantitative proportion of the fire-retardant additive is from 0 to 3% by weight, and - where the fire-retardant additive in essence has been mixed uniformly into the polymer matrix and where fire-retardant additive used comprises melamine phosphate and/or melamine polyphosphate and/or melamine cyanurate and - where the outer layer or the belt core of the belt comprises the first material A and - where the substructure of the belt with the force-transmission zone or the belt shell comprises the second material B. - a belt structure made of a polymeric material with elastic properties, encompassing an outer layer as belt backing and a substructure with a force-transmission zone ; and - a tension-member system embedded in the belt structure; characterized in that the belt structure is composed of at least two different materials A and B, namely of: - a first material A which comprises a fire-retardant additive and which has been incorporated in the belt structure wherever there is no requirement for the high level of mechanical properties; where the quantitative proportion of the fire-retardant additive is from 5 to 50% by weight; and - a second material B which has low, or no, content of a fire-retardant additive and which is used in the belt-structure region which is subject to the highest level of mechanical requirements, where the quantitative proportion of the fire-retardant additive is from 0 to 3% by weight, and - where the fire-retardant additive in essence has been mixed uniformly into the polymer matrix and where fire-retardant additive used comprises melamine phosphate and/or melamine polyphosphate and/or melamine cyanurate and - where the outer layer or the belt core of the belt comprises the first material A and - where the substructure of the belt with the force-transmission zone or the belt shell comprises the second material B. - a first material A which comprises a fire-retardant additive and which has been incorporated in the belt structure wherever there is no requirement for the high level of mechanical properties; where the quantitative proportion of the fire-retardant additive is from 5 to 50% by weight; and - a second material B which has low, or no, content of a fire-retardant additive and which is used in the belt-structure region which is subject to the highest level of mechanical requirements, where the quantitative proportion of the fire-retardant additive is from 0 to 3% by weight, and - where the fire-retardant additive in essence has been mixed uniformly into the polymer matrix and where fire-retardant additive used comprises melamine phosphate and/or melamine polyphosphate and/or melamine cyanurate and - where the outer layer or the belt core of the belt comprises the first material A and - where the substructure of the belt with the force-transmission zone or the belt shell comprises the second material B. <EOS>