It runs from Bagby Street in Downtown and terminates at the Westpark Tollway on the southern edge of George Bush Park, stretching about 19 miles (31 km) long.

The portion spanning from I-610 west to the Westpark Tollway is designated as a part of Farm to Market Road 1093 (FM 1093).

John Nova Lomax of the Houston Press said in a 2006 article that Westheimer Road, "more than any other thoroughfare, embodies Houston's car-enamored, zoning-free ethos, a damn-near 20-mile [32 km] phantasmagoria of strip malls, storage facilities, restaurants, big-box retail, office parks, apartment complexes, strip clubs, malls, supermarkets and the occasional church.

"[4] In another article, he referred to Westheimer as "mainly about the fetishes, broken dreams and vanities of Anglo whites.

Middle-class subdivisions of the 1950s flank this strip, but they are hidden behind broad bands of commercial development that face Westheimer.

Not only do shopping centers, gas stations and fast-food restaurants line up along Westheimer—each flashing signs or theme-style inducements to passersby—but mega-garden apartment complexes compete for attention in a mixture of dimly recognizable 'traditional' styles.

"[7]Lomax said that the segment of Westheimer in Westchase is "virtually all chains—a Geography of Nowhere wasteland of Boston Market, Borders, Kroger, Randalls, Taco Bell, Citgo and Sonic.

[9] In 2007, Mimi Swartz of Texas Monthly referred to a stretch of Westheimer between Claremont Lane and Kirby Drive as "the socialite's sector" due to the stores catering to residents of River Oaks and other nearby wealthy communities; in the article, she describes several places along the stretch of Westheimer.

Brands that feature boutiques include Apple, Tom Ford, Gucci, Fendi, Christian Dior SE, Dolce & Gabbana, John Hardy, Cartier, Carolina Herrera, Prada, Rolex, Versace, etc.