Some of those caught up in the shooting have spoken about it for the first time in a documentary, and said they are determined to be defined by what they do in life rather than what happened to them.
Amy Hutchison was part of the primary one class that was targeted by Thomas Hamilton in the gym hall of Dunblane Primary School on March 13, 1996.
He killed 16 young pupils and their teacher Gwen Mayor before turning the gun on himself.
Dunblane: Our Story, to be screened by the BBC days before the 20th anniversary of the tragedy, hears from 25-year-old survivor Ms Hutchison as well as head teacher Ron Taylor and the family of some of the victims.
Ms Hutchison was shot in the leg and treated in hospital for six weeks.
She said: “As a child the anger was not there, but looking back now I think ‘why?’ Why my class, why my school, why my town? Why?
“I don’t remember the pain of being shot, I don’t remember the noises or sounds, I just remember my leg turning to jelly and falling to the floor and then dragging myself to the gym cupboard where there was other people.”
Doctors had suggested skin grafts on her left leg in later life to cover scarring caused by the gunshots, but she said: “To me that wasn’t an option – these are my scars, they’re on my body, it’s my story, so I’m not going to hide them. I’m not ashamed of them.”
Mr Taylor said the “unimaginable” images from the day still live with him.
He told the documentary: “I just couldn’t believe what I was seeing. It was unimaginably horrible to see children dying in front of you.
“Seeing the staff tending to the injured, seeing the bodies of those who had died – in that moment the enormity of the event hit me. That moment has never left.”
To help him cope, Mr Taylor wrote down his memories of the day and stored them in a box in his house – but he has never opened it.
He added: “This event was so unprecedented and so huge with so many implications for so many people that we really must mark this important anniversary.
“It’s very difficult for the community and many people might not agree with me, but it’s hugely important to help as best we can those who survived and support those who lost.”
Alison Ross, the teenage sister of victim Joanna Ross, said it is hard to cope at times but she wants people to see the positive life in Dunblane today.
“It looms over us all I think and it gets a bit hard to accept,” she said.
“Even something as simple as her brushing my hair for me – it just isn’t there. It always makes me wonder the relationship we could of had. It’s just not available now, it’s not there at all.”
She added: “It needs to be remembered so that everyone’s aware that we are still here, we are still getting on with our lives and we didn’t just fade into the background either. We still had to power on and push on with our lives and it’s important that everyone knows we’re doing it, and doing it well.”
Dunblane: Our Story will be broadcast on BBC Two and BBC One Scotland at 9pm on Wednesday.