Bang & Olufsen (B&O) is a Danish high-end consumer electronics company that designs and manufactures audio products, television sets, and telephones, originally from Denmark, founded in 1925 by Peter Bang and Svend Olufsen, who designed a radio to work with alternating current, a product of significance at a time when most radios were still running on batteries.

When he returned to Denmark, he collaborated with his friend Svend Olufsen (1897–1949), whose parents made the attic of their manor house in Struer in Jutland available for experiments.

There were a number of successful developments in the 1930s and 1940s, including a sound recording system for the film industry, roof-mounted loudspeakers for circuses and army vehicles, and the iconic Beolit 39 radio that featured a Bakelite cabinet.

The firm suffered a major setback towards the end of World War II when its factory at Gimsing [da] was burnt down by pro-Nazi saboteurs as a punishment for the management's refusal to team up with the Germans.

Undeterred, Bang and Olufsen rebuilt the factory, and they produced electric razors until 1955, and then moving on to develop a range of radio, radiogram, and television sets, that was influenced later by a designer named Ib Fabiansen who began work for the company in 1957.

In January 2020, Bang & Olufsen A/S reported its third consecutive quarterly loss as the Danish hi-fi maker struggled with a buildup of inventory after consumers balked at buying $500 headphones.

Its midrange and treble drivers use the audio lens technology developed by Sausalito Audio's Manny LaCarrubba to spread the sound over a 180-degree range in order to fill the room, overcoming the directional range limitations of normal midrange and treble drivers, and preventing the sound from reflecting off the ceiling and floor before reaching the listener.

[19] In addition to consumer products the company also produces business-to-business services, particularly in the area of custom audio-visual installations for car manufacturers, and the hospitality industry.