The invention provides a wind turbine blade comprising a first shell, having a first bonding region, and a second shell having a second bonding region, wherein the second bonding region of the second shell is bonded to the first bonding region of the first shell; and a temperature sensor positioned between the first bonding region and the second bonding region. Having a temperature sensor positioned within the turbine blade, in the region at which the two shells of the turbine blade are bonded together, allows for accurate determination and control of the temperature of the critical bonding regions during blade manufacture. The temperature sensor may be used during the service life of the wind turbine blade to detect delamination of the wind turbine blade.
