Child Wise is one of Australia's leading not-for-profit child protection and child safeguarding agencies.
Save the Children Australia CEO Paul Ronalds said the two organisations had a shared mission to protect the rights of children.
"We can achieve more in scale and impact for vulnerable children working together as one agency," Mr Ronalds said.
"With evidence-based practice and research underpinning the Child Wise programs, this partnership with Save the Children makes good strategic sense.
It provides an excellent opportunity to broaden and strengthen our child protection programs and build capacity in the wider community so that individuals and organisations know what steps to take to keep children and young people safe from abuse and harm."
While new Australian charities are being created every year, this is Save the Children's third merger in as many years.
"We believe the sector needs to consolidate to create greater impact and leverage economies of scale," Mr Ronalds said.
"We believe working together strengthens the sector and creates more opportunity to deliver services."
The merger is consistent with recommendations from the Royal Commission into Institutional Responses to Child Sexual Abuse interim report, which highlighted the need for shared responsibility and collaboration in child safety across of all levels of society.
Established in 1991, Child Wise is dedicated to protecting children from abuse and exploitation – both in reducing the incidence and impact.
Child Wise works to protect children from abuse through education, researching and responding to emerging risks to children and young people, and helping to shape regional and national policy through advocacy and partnerships.
The merger will be finalised on December 31.
Child Wise chair Andrew Blode said the move would increase the reach and scale of Child Wise programs.
"It has the potential to significantly increase the availability of groups within Australian society to access child protection and safeguarding expertise to keep children safe from harm," Mr Blode said.
"The Royal Commission Inquiry has raised awareness and now organisations and the general community are tightening their policies to keep children and young people safe from abuse and harm.
"I have no doubt that this next step with Save the Children will accelerate the vision to create a safer community for children and young people."
Save the Children's Paul Ronalds said the coming together of the child rights sector served to strengthen advocacy and services delivery for vulnerable children in Australia and internationally.
"This partnership is a positive step toward a better future for children," Mr Ronalds said.
"We are excited about the opportunity through this partnership to take Child Wise safeguarding training into the Pacific and other neighbouring countries where we know there is a real need."
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