Since it began - with the slogan Back to Sleep - 1991, the number of cot deaths has fallen by 75% in Britain, saving an estimated 14,000 babies' lives.
Most people now follow the advice to put babies to sleep on their backs, rather than their tummies at the bottom of the cot.
But, according to experts, a new danger has emerged.
There has been a huge increase in the number of babies who die when their parents doze off with them on the sofa.
About 30 babies died in this way over the past year - and now it's led to a new campaign to make sure parents are aware of the dangers.
Caroline described how she discovered that her baby son Thomas had died:
"My twins were born as a result of IVF. Thomas was the bigger of the two and was also a very hungry feeder.
"I had fed both of them; I put Joseph back in the cot, but Thomas wanted more.
"We both fell asleep and when I woke up two hours later - because Joseph woke up - Thomas felt very still.
"When I checked him, he didn't look right. He'd died in the bed."
HOW TO REDUCE COT DEATH RISK
Cut smoking during pregnancy - fathers too
Do not expose your child to smoke
Put your baby to sleep on its back, feet to foot of the cot
Keep your baby cool, with its head uncovered. Don't use duvets or cot bumpers
Don't share a bed with your baby if you're very tired, smoke or have been drinking
Sleep in the same room as your baby for the first six months
Never fall asleep with a baby on a sofa or armchair
If your baby is unwell, seek medical advice promptly
To this day, Caroline doesn't know exactly why Thomas died. She does know from the postmortem that he didn't suffocate and she always followed safety advice about not letting your baby overheat.
After his death, she told us, she has always chosen the most uncomortable chair to feed her babies in, so she'd never fall asleep again.
According to cot death campaigner, Joyce Epstein, sleeping with your baby in bed is far less dangerous than dozing off on the sofa.
"Bring the baby into bed for feeds and cuddles, but put the baby back in his cot to go to sleep," she said.
A team from Bristol Royal Children's Hospital, which has been studying sudden infant deaths, is warning that cot deaths don't always happen in a cot.
They have discovered that around 30 babies each year die when they're sharing a sofa or armchair with a parent who dozes off.
A further 135 babies died last year when they were sharing a bed with their parents.
The study also found more deaths are occurring among poor families, and among those where the mother
The researchers are worried that some mothers may have misunderstood the advice not to take the baby into bed.
They believe mums may be getting up to feed babies on the sofa, then falling asleep because they're so tired.
Prof Peter Fleming told Breakfast: "It's actually far more dangerous (to fall asleep on the sofa) than having the baby in bed in the first place."
It is already known that the risk of sudden infant death syndrome (SIDS) is higher for babies that are born premature, or have a low birthweight.
Male babies also appear to be more at risk, as do those who sleep on their side or front.
Smoking during pregnancy, or in the house after a child is born, is another risk factor.