ISO 16329:2003 specifies the structure, performance, inspection and testing of heading control systems to be installed on board crafts operating under the following conditions:

1. speed exceeding 30 kn and up to 70 kn;
2. maximum rate of turn 20°/s;
3. the normal range of operation between 70°N and 70°S should, as required by chapter 13 of the HSC Code, comply with the minimum performance requirements specified in these standards.

ISO 16329:2003 applies to the heading control systems which enable a craft to keep a preset heading with minimum operation of the craft's steering gear, within limits related to the craft's manoeuvrability in conjunction with their sources of heading information.