The show runs for approximately ten minutes, organised into five themed movements. It opens with 'Awakening' — flashes and pulses of light suggesting the city coming alive — before moving through 'Energy,' a high-intensity sweep of lasers and searchlights across the night sky, and 'Heritage,' where the buildings shift to traditional lucky red and gold as Chinese musical instruments enter the soundtrack. 'Partnership' follows, with beams reaching across the water as if connecting the two shores, and the finale, 'Celebration,' closes the show with kaleidoscopic patterns that swirl and multiply across the full harbour panorama.

The show was conceptualised, created, and installed by LaserVision and is organised nightly by the Hong Kong Tourism Board. Since launching on 17 January 2004 with 18 buildings on the Hong Kong Island shore, it has expanded considerably. By 2007, 47 buildings on both sides of the harbour participated. As of 2022, the number stood at 39 buildings and two attractions. The narration broadcast from vantage points on the waterfront rotates among English, Mandarin, and Cantonese depending on the night of the week.

The best viewing requires being on the water's edge rather than above it. The Avenue of Stars on the Tsim Sha Tsui waterfront — the Kowloon shore — offers an unobstructed view of the Hong Kong Island skyline lighting up across the water; this is where the live narration and music play. The promenade outside Golden Bauhinia Square in Wan Chai on the Hong Kong Island side offers the reverse perspective, looking north toward the Kowloon hills as the Kowloon buildings join the display.

For the most immersive experience, many visitors board one of the Star Ferry's sightseeing crossings during the show, allowing the harbour to surround the spectacle on all sides. The show is suspended when Tropical Cyclone Warning Signal No.3 or above is issued, or when a Red or Black Rainstorm Warning is in effect from 3 pm onward — so on the stormiest evenings, the harbour goes dark. It is also suspended on official days of mourning, as it was in October 2012 following the Lamma Island ferry disaster.

The show takes on additional scale on special occasions. For New Year's Eve, A Symphony of Lights has typically been augmented with pyrotechnics launched from rooftops across both shores, turning the standard 10-minute programme into a full midnight celebration broadcast to the world. After the 2019 protests raised security concerns, the 2019 New Year's Eve fireworks were cancelled for the first time in a decade; an enhanced version of the light show served as the midnight celebration instead, with the Hong Kong Convention and Exhibition Centre facade transformed into a countdown clock.

Following a four-year hiatus, the New Year's Eve fireworks returned on 31 December 2023 in what was reported as the largest and most spectacular display since 2019, spanning 1,200 metres across the harbour from Central to Causeway Bay. The show was directed by Liu Lin, Chief of the Fireworks Project and Director of Fireworks Operations for the Opening and Closing Ceremonies of the 2008 Summer Olympics in Beijing.

What makes A Symphony of Lights unusual among the world's light shows is not the technology — major cities have mounted more elaborate one-night displays — but its permanence. The infrastructure, the programming, the nightly coordination of dozens of independent buildings, has been sustained for over two decades. Hong Kong's skyline, already one of the most recognisable in the world, performs on a schedule.

There is an irony worth noting. The show has occasionally become a lens through which to read the city's politics: cancelled during mourning, adapted when protest-era security concerns arose, used as a vehicle for handover anniversary celebrations. The buildings that participate include the headquarters of major banks, the Convention Centre where sovereignty was transferred in 1997, and the offices of the Chinese People's Liberation Army. They illuminate together each night regardless, the harbour as spectacular as ever.