This paper investigates the addition of paper making reject fibre into pilot scale MDF panels with the aim of creating cost savings in board manufacture, without compromising board properties. The contamination of the paper rejects by trace metals was assessed and determined not to be an impediment to use of the material in panels. Dried paper rejects were added to the board furnish in varying amounts. Initial trials utilising 0.25m2 boards showed a positive results in terms of improved MOR and MOE when adding paper rejects. On up scaling to 1m2 boards this positive effect was reduced to non- significant levels. However, there was no significant reduction in board properties at the highest levels of reject fibre addition. This suggests that waste paper rejects may be used to reduce the amount of wood fibre in MDF without compromising board properties.