The latest phase of the Department of Transportation's "LOOK!" campaign aims to protect the City's cyclists and taxi passengers with stickers posted on cab windows.
The stickers remind passengers to look before opening the door in an effort to avoid hitting an oncoming cyclist.
Transportation officials say at least seven cyclists have been killed and many more injured by so-called dooring accidents since 2007.
"I got two accidents in 10 years," said taxi driver Zafar Ahan. "Two doors, I've damaged the doors, and passenger was not hurt. The cyclist was hurt."
"It just takes one second as you're fumbling for the change and you're calculating the trip, before you get out, just take that one second and look before you get out of the cab," said Transportation Commissioner Janette Sadik-Khan.
The safety campaign will also be featured on taxi TVs.