The slip direction and slip sense of a fault constrain the orientation of the stress field that caused the fault to slip. Inversion of such slip data for populations of minor faults to determine ancient stress fields is a well-established technique in structural geology. In the field and in oriented core, the slip direction and slip sense of minor faults are typically determined by observation of fault-surface morphology. Because fault surfaces are not visible in image logs, subsurface paleostress analysis based on inversion of mesoscopic fault data has only been possible with oriented cores. This contribution describes how to work with faults with associated pinnate joints to determine the slip sense and slip direction of a fault based only on observations made in image logs.