A method and apparatus for measurement of a characteristic of a substrate. A target is present on the substrate and a measurement is performed during a scanning movement of the substrate. The scanning movement of the substrate is a linear movement and the measurement includes obtaining a reflected image of the target using a pulsed light source, the duration of a single light pulse being less than 100 psec. A lithographic apparatus includes such a measurement apparatus, and a device manufacturing method includes such a measurement method.