This master thesis studies the early concept development process of fiber reinforced composites. The process and the challenges of such a development have been demonstrated through a case study at GKN Aerospace developing a fiber reinforced composite core fairing of a jet engine, currently made out of titanium honeycomb sandwich. The operation environment on such a component is extreme and high temperatures, fire risks, vibrations and fatigue are just some of the challenges which the new fiber reinforced composite will have to withstand. The case study included the detailed investigation of various challenges in the three technology areas of functional design, materials selection and manufacturing selection with the aim of finding valid concepts for the continuing development. The concepts were aiming at fulfilling the Technology Readiness Levels of 3-4.The result of the thesis demonstrated the importance of early identifying the challenges which could eliminate potential concepts within the targeted TRL. The importance of simultaneous evaluation throughout the process was also realized. Because of the closely integrated technology areas, no choice could be made without affecting the other areas at the same time. The study also showed the consequence of not reaching the same maturity of these three engineering fields when evaluating the concepts. Without a comparable maturity, the concepts consisting of the same technology areas are not complete and the subsequent concept selection is not possible without further investigation.