This work was motivated initially by the desire to develop fully bioresorbable bone plates for fracture fixation applications, in order to meet a clinical need. The purpose of the development is to avoid medical complications related to rigid, non-resorbable metallic bone plates. Phosphate based glass fibre reinforced poly-lactic acid (PGF/PLA) composites containing fully biodegradable and biocompatible constituents can be an effective alternative to metallic bone plates. Appropriate design and manufacture of the PGF IPLA composite bone plates is crucial to ensure that the required mechanical and degradation properties are achieved for the support of bone healing. Rather than considering simply the material propelties of the PGF/PLA composites, it is necessary to take into account all the factors relating to surgical use: constrained plate dimensions, bone topography and contact area, fixation method, sterilisation method, local environment and overall nature of the loading case. Each of these factors will have a profound effect on the design of the composite. In this PhD, studies have been undertaken to develop and produce a PGF/PLA composite bone plate that can fulfil the requirements of a specific application. The composite plates were prepared by using an optimal combination of unidirectional and random fibre reinforcement, before being trimmed and drilled into a desired final geometry. To validate the composite design, mechanical and degradation properties, in vitro mechanical and biomechanical testing were combined with preclinical in vivo testing using an intact rabbit tibia bone model.