In this paper, an adaptive interval type-2 fuzzy controller is proposed for variable-speed and variable-pitch wind turbines. Because of attractive features of the well-known wind turbine baseline controller, the proposed controller acts as an augmented controller and works in parallel to the baseline controller. As typical variable-speed wind turbines have different controllers for different operation regions, for each operation region, a dedicated interval type-2 fuzzy controller is designed. Because of the uncertainty in wind speed measurement, modern control techniques try to estimate this value. However, in contrast to these modern control techniques, the proposed controller is independent of the wind speed estimation. Thus, there is a better saving in cost and computational burden. To evaluate the effectiveness of the proposed controller, simulations are conducted with wind profiles which span all operation regions. Results show that, compared with the baseline controller, the proposed controller enhances power generations and reduces mechanical loads concurrently.