Sign spinning is a controversial form of outdoor advertising in which trained employees stand on public street corners and display surfboard-sized cardboard signs. These signs are generally sponsored by local companies in the general vicinity of the sign spinner, but national companies have been known to invest in sign spinning services to reach a younger demographic. Sign spinning involves a combination of acrobatics, baton-tossing and martial arts movements designed to attract the attention of passing motorists.

Sometimes called "human directionals," sign spinners are generally young and eager to take on non-traditional careers. Advertising companies such as Aarrow Advertising in San Diego routinely recruit and train interested sign spinners, with professional instructors teaching new employees new sign spinning moves in a camp setting. Once a sign spinning recruit has demonstrated a mastery of the basic maneuvers, he or she is provided with a sponsored sign and assigned a location. Sign spinning beginners could earn $10 to $20 US Dollars (USD) per hour, but more skilled spinners or instructors sometimes earn up to $60 USD an hour.

Some say sign spinning is an ideal way to gain much needed attention from passing motorists, since a static sign eventually loses its appeal over time. A good sign spinner can attract a crowd of pedestrians with his or her stunts, generating word of mouth advertising and interest in the product or company name. Sign spinning also returns a personal element to the world of advertising, since a real person is providing entertainment along with the sales pitch.

Others say sign spinning should not be seen as a viable form of advertising. The signs and the stunts can easily cause drivers to become distracted, and the sign spinners themselves may be in danger of being struck. While sign spinning may attract some attention, the message may not be registering with potential customers as well as advertisers may hope. If the sign spinners do not allow enough time for passers-by to read the copy, then the exercise may be pointless. Some cities have already passed legislation banning sign spinning on public streets.

There is also a safety concern with sign spinning, since many advertising companies often compete for the same popular street corners. Some sign spinners have been assaulted or harassed by rivals seeking exclusive rights to a particularly good location. Passing motorists may also express their disinterest with sign spinning by throwing food or shouting obscenities at the spinners themselves. Sign spinning can be a hazardous profession, and some smaller advertising agencies have been known not to pay their employees for their services. As with other types of guerrilla advertising techniques, it pays to know who you're dealing with before taking on a sign spinning assignment.