PBSmapping: Mapping Fisheries Data and Spatial Analysis Tools. This software has evolved from fisheries research conducted at the Pacific Biological Station (PBS) in Nanaimo, British Columbia, Canada. It extends the R language to include two-dimensional plotting features similar to those commonly available in a Geographic Information System (GIS). Embedded C code speeds algorithms from computational geometry, such as finding polygons that contain specified point events or converting between longitude-latitude and Universal Transverse Mercator (UTM) coordinates. Additionally, we include C++ code developed by Angus Johnson for the Clipper library. PBSmapping also includes data for a global shoreline and other data sets in the public domain. The R directory ‘.../library/PBSmapping/doc’ offers a complete user’s guide PBSmapping-UG.pdf, which should be consulted to use all functions in the package effectively.