on the front line of (something)

leading others in an effort to change something.

For years the group has been on the front line of efforts to educate people about global warming.

Doctor Tay is on the front lines of improving treatment for people with head and spinal injuries.

Etymology: based on the military use of soldiers on the front line or front lines (= closest to the enemy and very important but also those most likely to be hurt or killed)

• the darkest hour is just before the dawn.
• the day of reckoning
• the dead hand of
• the dead hand of something
• the death knell
• the demon drink
• the devil finds work for idle hands.
• the devil take the hindmost
• the dice are loaded against
• the dice are loaded against someone
• the die is cast
• the dog days
• the done thing
• the dreaded lurgy
• the dust settles
• the early bird catches the worm.
• the earth moved
• the ebb and flow
• the ebb and flow of
• the ebb and flow of something
• the end justifies the means.
• the end of the line
• the end of the road
• the eye of the storm
• the factory floor