A key factor determining the performance of carbon fibre reinforced polymer (CFRP) composites is their fibre-to-matrix interactions, the interface and interphase, as these allow for the efficient transfer of stress from the relatively weak and ductile resin to the strong reinforcing fibres. The manipulation of the interface via modulation of surface chemistry has been an active area of research with many approaches being taken. In this work we cover efforts in this area from traditional manufacturing condition optimisations, plasma, wet chemical, and electrochemical approaches to induce favourable properties in composites. The design of molecular interactions at the interface are exceedingly difficult to determine and design, and thus, we finish this review with a section on the use of molecular dynamics to design complementary interfaces for the next generation of composites.