This manual discusses the use and interface of the GibbsCAM Radial Milling option (formerly Ò4-AxisÓ). The Radial Milling module provides simultaneous 4-axis machining of 3D geometry including support for Y-axis offsets. Recommended prior reading: Geometry Creation; Mill; and either 2.5D Solids or SolidSurfacer if you will be working with solids. Last major update (other than name change from Ò4-AxisÓ): September 2009, for GibbsCAM 2009, v9; last revised January 2015, for GibbsCAM 2015, v11.0