A working methodology to minimize wellbore stability problems has been established through the use of unique laboratory tests, an experimental database for fluid-rock interaction and physical properties of shales, and an integrated modeling approach utilizing different types of experimental and field data. The model simulations provide output accounting for a wide range of input parameters such as well inclination, mud chemistry, rock mechanical properties, field stresses and pressures, formation anisotropy, and shale mineralogy. The model output can subsequently be used to diagnose field drilling problems or to design drilling operations. As an example, data from a high pressure/high temperature (HP/HT) field offshore Mid-Norway as well as a field in the overpressured shales in the southern part of the Norwegian North Sea have been analyzed and compared.