A gambling reform summit is taking place in Sydney as campaigners in Australia look at ways to curb high rates of addiction.
It is estimated there are 300,000 problem gamblers in Australia - the equivalent to the population of the national capital, Canberra.
Australia's gambling industry generates about A$18bn ($15bn:£10bn) annually.
Campaigners meeting in Sydney say slot or fruit machines lie at the heart of a "social emergency".
Australians are inveterate gamblers and vast amounts of money - more than US$8bn - are poured every year into the "pokies".
Problem gambling has cost those caught in a spiral of addiction and debt their jobs, homes, marriages and even their lives.
The gambling reform summit has heard repeated calls for the government to do more to protect the vulnerable from the temptations of Australia's lucrative betting industry.
Independent Senator Nick Xenophon says immediate action is needed and the industry "needs to realise that its time is up".
"They can't continue to go with business as usual. It is not tenable for a situation where 50% of poker machine losses come from problem gamblers and something has to change," he said.
"There are literally hundreds of thousands of Australians today whose lives are worse off because of a poker machine addiction, either directly or through a member of their family and this is something that we cannot ignore as a very major social issue."
Australia's gambling industry says it is committed to promoting a sensible approach to betting.
Leaflets and mandatory warnings on poker machines urge players to know their limits and give details of telephone helplines for those with problems.
A government report on the social consequences of gambling in Australia is expected to be released in the next few months.