The effect of reinforcing fibres on the morphology of a thermoplastically toughened tri-functional epoxy resin cured with an aromatic hardener has been studied using optical microscopy. Single and multiple strands of different types of fibres were placed within curing resin matrices containing varying thermoplastic concentrations. The fibres appeared to encourage the development of large particles (significantly larger than would be found in the bulk matrix), which remained at the fibre surface. A plain weave glass fibre tape was also found to greatly affect the final morphology of the same system. The results indicate that the morphology of a thermoplastic modified epoxy/amine resin is significantly affected by reinforcing fibres.