A motor vehicle having: prime mover means; a first pair of wheels (12, 13); a second pair of wheels (14, 15); a driveline operable to connect the prime mover means to the first pair of wheels (12, 13) and the second pair of wheels (14, 15) such that the first pair of wheels (12, 13) and not the second pair of wheels (14, 15) is driven by the prime mover means when the driveline is in a first mode of operation and the first and second pairs of wheels are driven by the prime mover means when the driveline is in a second mode of operation, the driveline including: an auxiliary portion comprising releasable torque transmitting means (22, 27) by means of which the driveline is operable to connect the second pair of wheels to the prime mover means when the driveline transitions from the first mode of operation to the second mode of operation, and a controller comprising a control module, the control module being configured to control the vehicle transition between the first mode of operation and the second mode of operation; wherein when in the first mode of operation the driveline is operable to transition from the first mode of operation to the second mode of operation responsive to an output of a reactive evaluator and a predictive evaluator, wherein the output of the reactive evaluator is responsive to a determination whether an amount of wheel slip has exceeded a first prescribed threshold, wherein the output of the predictive evaluator is responsive to a determination whether one or more conditions in respect of one or more vehicle operating parameters are met when the amount of wheel slip is below the first prescribed threshold; and wherein the predictive evaluator is configured to provide a further output signal to the control module, wherein the further output signal is configured to: provide an indication that the transition from the first mode of operation to the second mode of operation has been triggered by the predictive evaluator, and provide an indication as to a corresponding rate at which said transition to the second mode of operation should be made. prime mover means; a first pair of wheels (12, 13); a second pair of wheels (14, 15); a driveline operable to connect the prime mover means to the first pair of wheels (12, 13) and the second pair of wheels (14, 15) such that the first pair of wheels (12, 13) and not the second pair of wheels (14, 15) is driven by the prime mover means when the driveline is in a first mode of operation and the first and second pairs of wheels are driven by the prime mover means when the driveline is in a second mode of operation, the driveline including: an auxiliary portion comprising releasable torque transmitting means (22, 27) by means of which the driveline is operable to connect the second pair of wheels to the prime mover means when the driveline transitions from the first mode of operation to the second mode of operation, and a controller comprising a control module, the control module being configured to control the vehicle transition between the first mode of operation and the second mode of operation; wherein when in the first mode of operation the driveline is operable to transition from the first mode of operation to the second mode of operation responsive to an output of a reactive evaluator and a predictive evaluator, wherein the output of the reactive evaluator is responsive to a determination whether an amount of wheel slip has exceeded a first prescribed threshold, wherein the output of the predictive evaluator is responsive to a determination whether one or more conditions in respect of one or more vehicle operating parameters are met when the amount of wheel slip is below the first prescribed threshold; and wherein the predictive evaluator is configured to provide a further output signal to the control module, wherein the further output signal is configured to: provide an indication that the transition from the first mode of operation to the second mode of operation has been triggered by the predictive evaluator, and provide an indication as to a corresponding rate at which said transition to the second mode of operation should be made.