Numerical simulation of 3-D dynamic stall has been undertaken using computational fluid dynamics. As a first step, validation calculations have been performed for cases in which experimental data were available. Although the amount and quality of the experimental data available for 3-D dynamic stall does not match what is available for 2-D cases, the computational fluid dynamics was found capable of predicting this complex 3-D flow with good Accuracy. Once confidence on the computational fluid dynamics method was established, further calculations were conducted for several wing planforms. The calculations revealed the detailed structure of the 3-D dynamic stall vortex and its interaction with the tip vortex. Remarkably, strong similarities in the flow topology were identified for wings of very different planforms.