Protein engineered biosensors provide the next best step in the advancement of protein-based sensors that can specifically identify chemical substrates. The use of native proteins for this purpose cannot adequately embrace the limits of detection and level of stability required for a usable sensor, due to globular structure restraints. This review chapter attempts to give an accurate representation of the three main strategies employed in the engineering of more suitable biological components for use in biosensor construction. The three main strategies in protein engineering for electrochemical biosensor implementation are: rational protein design, directed evolution and de novo protein design. Each design strategy has limitations to its use in a biosensor format and has advantages and disadvantages with respect to each. The three design techniques are used to modify aspects of stability, sensitivity, selectivity, surface tethering, and signal transduction within the biological environment. Furthermore with the advent of new nanomaterials the implementation of these design strategies, with the attomolar promise of nanostructures, imparts important generational leaps in research for biosensor construction, based on highly specific, very robust, and electrically wired protein engineered biosensors.