This thesis investigates the performance of GFRP pretensioned concrete slabs and compares their flexural behaviour with GFRP reinforced and steel prestressed concrete slabs. A total of 12 slabs were cast in this program. The slab mid-span deflections are theoretically predicted and the results indicate that the short-term response of GFRP prestressed concrete slabs can be predicted well by the existing methods. Long-term deflection behaviour has been estimated using the Age Adjusted Effective Modulus Method by incorporating three creep and shrinkage models. A large influence of creep and shrinkage models on the theoretical determination is observed and the use of long term multipliers is not suitable for GFRP prestressed concrete members. The slabs were instrumented for long-term monitoring using strain gauges and fibre-optic sensors. It was concluded that the electrical strain gauges can be successfully used for long-term strain monitoring.