When an excavation is made in soil or rock, materials adjacent to the cut face lose their natural lateral support. It then becomes necessary to support the excavation by using braces and tiebacks. These will provide the lateral restraint needed for safety. These guidelines have been prepared to aid civil engineers in making the essential decisions regarding construction safety and excavation activities. They are also intended to provide information and conceptual orientation for owners, funding agencies, contractors, and engineering and architectural staff.