Ms Gallagher officially took the reins of mental health and housing portfolios for the federal Labor Party on Sunday, more than a month after she was promoted to the Opposition front bench and weeks after her new responsibilities were announced.

She paid homage to Senator Jan McLucas, due to retire at the next election, who she replaced in the role in the reshuffled shadow ministry.

"I am very excited to be taking up my new role today as shadow minister for mental health as well as shadow minister for housing and homelessness," Ms Gallagher said.

"I am indebted to the significant work undertaken by Senator McLucas over the past two years."

The newly minted frontbencher began her tenure by calling for more help for Australians who had been left behind.

Ms Gallagher cited "shocking" estimates that 3.6 million Australians would experience mental health problems every year.

That number rises to 7.3 million people who will experience a mental health issue at some point in their lives.

"Every year more than 65,000 Australians will attempt suicide, with more than 2500 dying every year from suicide. And it is hard to accept that suicide is the leading cause of death for people aged between 15 and 44 years old," Ms Gallagher said. "These statistics are staggering."

In the coming months, the government is expected to respond to a report into Australia's mental health system which it received about one year ago.

Ms Gallagher urged the Turnbull Government to heed the report and make mental health reform a priority.

"Every day that responsibility for mental health reform is put off is another day that those people living with a mental illness, those who care for them and those who work in the sector are being let down.

"Labor has already committed to providing better support for people with a mental illness."

She said Labor initiatives included committing to a target to reduce suicide by 50 per cent over the next 10 years, develop an Aboriginal and Torres Strait Islander mental health plan, improve the economic participation of people living with a mental illness, and restore the Mental Health Commission's independence.

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