A sensor, preferably for magnetic rotary or linear sensor systems, includes a scale situated at a specified distance from the sensor, and having at least one magnetic field-sensitive GMR sensor element provided in a housing, the housing also having one magnetic field source respectively associated with the at least one GMR sensor element, the magnetic field source being accommodated in a shield enclosing same in a U-shape, and the magnetic field source, the at least one GMR sensor element, and/or the housing being tilted at a specified distance and by a predetermined angle relative to the reference plane of the scale.