This Standard provides a uniform basis for the design, detailing, fabrication, testing, assembly, and erection of steel tubular structures for electrical transmission poles. These guidelines apply to cold-formed single- and multipole tubular steel structures that support overhead transmission lines. The design parameters are applicable to guyed and self-supporting structures using a variety of foundations, including concrete caissons, steel piling, and direct embedment. Standard ASCE/SEI 48-11 replaces the previous edition (ASCE/SEI 48-05) and revises some formulas that are based on other current industry standards. This Standard includes a detailed commentary and appendixes with explanatory and supplementary information. This Standard will be a primary reference for structural engineers and construction managers involved in designing and building electrical transmission lines, as well as engineers and others involved in the electric power transmission industry.