Sailing Directions is a 42-volume American navigation publication published by the National Geospatial-Intelligence Agency (NGA). Sailing Directions consists of 37 Enroute volumes, 4 Planning Guide volumes, and 1 volume combining both types. Planning Guides describe general features of ocean basins and country-specific information such as firing areas, pilotage requirements, regulations, search and rescue information, ship reporting systems, and time zones, to name a few; Enroutes describe features of coastlines, ports, and harbors.
Sailing Directions are updated when new data requires extensive revision of an existing text. These data are obtained from several sources, including, but not limited to, pilots and Sailing Directions from other countries.
One book comprises the Planning Guide and Enroute for Antarctica. This consolidation allows for a more effective presentation of material on this unique area.
Sailing Directions (Planning Guide) and Sailing Directions (Enroute) are frequently updated. In early 2005, NGA discontinued production of these publications in printed form; subsequent editions were distributed in digital form only. Between editions, Sailing Directions are corrected via a binary patch process referred to as Publication Data Update (PDU).
Figure 1 shows an overview of Sailing Directions coverage.
Sailing Directions (Planning Guide) 
Planning Guide volumes assist the navigator in planning an extensive oceanic voyage, as well as giving information on individual countries that is applicable to all ports in those countries. Each of the Planning Guides covers an area determined by an arbitrary division of the world's seas.
Individual Planning Guides are divided into Countries and Ocean Basins, as follows:
- Pub. 120--51 Countries and 1 Ocean Basin (Pacific Ocean).
- Pub. 140--87 Countries and 6 Ocean Basins (Baltic Sea, Black Sea, Caribbean Sea, Mediterranean Sea, North Atlantic Ocean, and North Sea/English Channel).
- Pub. 160--61 Countries and 3 Ocean Basins (Indian Ocean, South Atlantic Ocean, and Red Sea/Persian Gulf).
- Pub. 180--5 Countries and 1 Ocean Basin (Arctic Ocean).
Country entries may contain information on the following subjects—Buoyage Systems, Currency, Firing Areas, Fishing Areas, Government, Holidays, Ice, Industries, Languages, Mined Areas, Navigational Information (to include maritime claims, maritime boundary disputes, and enroute volumes), Offshore Drilling, Pilotage, Pollution, Prohibited Areas, Regulations, Restricted Areas, Search and Rescue, Signals, Submarine Operating Areas, Time Zone, Traffic Separation Schemes, U.S. Embassy, and Vessel Traffic Services. Information that cannot be accurately depicted within the alphabeticized Country text may be listed as an Appendix at the end of the Country text.
Ocean Basin entries may contain information on the following subjects—Climatology, Currents, Fishing Areas, Geophysical Features, Ice, Ionospheric Disturbance, Magnetic Field, Meteoroloy, Mined Areas, Navigational Information, Optical Phenomenon, Pilotage, Pollution, Regulations, Routes, Seas, Ship Reporting Systems, Tides, and Surface Temperatures.
Figure 2 shows a typical Planning Guide page.
Sailing Directions (Enroute) 
Each Enroute volume contains numbered Sectors along a coast or through a strait. Each Sector is discussed in turn. A preface with detailed information about authorities, references, and conventions used in each book precedes the Sector discussions. A table showing conversions between feet, fathoms, and meters is provided. Finally, each volume provides a list of commonly-used abbreviations that may be found in the text.
The Chart Information Graphic, the first item in each Sector, is a graphic key for charts pertaining to a Sector. The graduation of the border scale of the chartlet enables navigators to identify the largest scale chart for a location and to find a feature listed in the Index-Gazetteer.
A foreign terms glossary and a comprehensive Index-Gazetteer follow the Sector discussions.
The Index-Gazetteer is an alphabetical listing of described and charted features. The Index-Gazetteer lists each feature by geographic coordinates and Sector-paragraph number.
The text of this article originated from sections 402 to 404 of The American Practical Navigator, a document produced by the government of the United States of America and amended by Marine Analysts at the National Geospatial-Intelligence Agency.
See also 
- American Practical Navigator
- Coast Pilots
- Light List
- List of Lights
- Local Notice to Mariners
- Notice to Mariners
- Chapter 4: Nautical Publications - from the online edition of Nathaniel Bowditch's American Practical Navigator
- All Enroute and Planning Guide volumes for PDF download
- Fast direct download of individual volumes - replace XYZ with Pub. Number
- Coast Pilots These nine volumes correspond to the Sailing Directions in the United States and Territories