Abstract: The present invention discloses an MWD system which permits an indirect measurement of the wellbore inclination angle at the drill bit, in situations where it is difficult or expensive to measure that angle directly. The system includes a first inclinometer included as part of a conventional directional sensor, which is located in the bottomhole assembly a relatively large distance above the bit. The first inclinometer provides a measure of the inclination angle .alpha. at point A. The system also includes a second inclinometer, which is provided closer to the drill bit to provide a measure of the inclination angle .beta. at point B. The inclination angles .alpha. and .beta. are used, together with bottomhole assembly configuration information, and other information relating to drilling tendencies, to determine with a reasonable degree of accuracy the inclination angle .theta. of the wellbore at the bit.