This article discusses bismaleimide (BMI) chemistry and the use of BMI in composites. An analysis of the applications illustrates how the advantages of BMIs have been exploited and perhaps suggests how these advantages might be extended to other applications. The article describes the mechanical properties of BMI composites. BMIs suitable for resin transfer molding processing are provided. The article concludes with information on the elevated-temperature applications of 5250-4 BMI system.