AASHTO LTS-6, Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals, 6th Edition (2013), governs the structural design of supports for highway signs, luminaires, and traffic signals. Section 1 introduces the scope, definitions, applicable specifications, and the types of structural supports covered, including sign, luminaire, and traffic signal supports and combination structures. General features of design, loads, and analysis and design considerations are treated in Sections 2 through 4. Material-specific design provisions follow for steel, aluminum, prestressed concrete, fiber-reinforced composite, and wood supports. Additional sections cover serviceability requirements, fatigue design, breakaway supports, and foundation design. The specifications serve as a standard and guide for the design, fabrication, and erection of these support structures by highway agencies and their consultants.