Abstract A new wellbore stability analysis method based on Quantitative Risk Analysis (QRA) principles is described in this paper. Limit state functions that define the limit for failure (stuck pipe due to excessive breakout) and success (operationally tolerable magnitudes of breakout) are defined as functions of wellbore trajectory and geometry. Stochastic input data for the QRA procedure, which incorporate uncertainties in model input parameters, are generated by a fully three-dimensional wellbore stability model. Modeling results yield probability of success as a function of drilling fluid density. A field application of the method is presented to illustrate the viability of the analysis.