OSXStereonet plots lines and planes in a stereographic, equal angle or equal area, projection. The program can produce various types of plots such as scatter plots, great circle plots, contour diagrams, rose diagrams, stereonets from any orientation, and plots of latitude-longitude data (e.g. coastlines). In addition, the program can perform various operations on data, including calculating poles to planes, rotating planes and lines, constraining lines to lie on respective planes, mean vector, cylindrical best fit, conical best fit, and angle between lines or planes. OSXStereonet is a modern Cocoa version of the popular Stereonet program by Richard Allmendinger. OSXStereonet has the same functionality as Stereonet, but in addition it has advantages such as a more intuitive interface to work with data, multiple lines and planes datasets, multiple stereonet documents, and enhanced speed and graphics.