I begin by acknowledging the traditional owners of the land, the Gadigal people of the Eora nation.
I also acknowledge tonight's host, Wayne Spanner, Managing Partner of Norton Rose Fulbright, and the person who is responsible for bringing us all together tonight, Farah Mohamed, CEO of the G(irls)20.
As Australia's Ambassador for Women and Girls, I'm privileged to meet incredible women from around the world on a regular basis.
But I'm always particularly pleased when my role allows me to meet with my equally important set of stakeholders: girls.
Being here this evening with the delegates to the G(irls)20 - and their supporters - reassures me that I am not alone in my long-held ambition for women and girls to be equal members in society.
Equally engaged in leadership and decision-making.
Equally engaged in economic life.
Sometimes I need that reassurance.
Despite progress over the past few decades, we know that many girls around the world are still faced with a very grim reality.
65 million girls across the world are out of school, and globally one in five girls of lower secondary school age is out of school
Every year, 10 million girls are forced or coerced into marriage - that's another girl every three seconds.
One in three girls in the developing world is married by the age of 18 and one in seven marries before they reach the age of 15
The leading cause of death for young women aged 15-19 in developing countries is pregnancy–a girl in Southern Sudan is more likely to die in child birth than she is to finish primary school.
150 million girls (and 73 million boys) under the age of 18 have
experienced rape or other forms of sexual violence.
There are compelling reasons to focus on the lives of women and girls in order to address these challenges facing entire communities.
But we also know that an extra year of a mother's schooling cuts infant mortality by 15-25 per cent.
An increase of only one per cent in girls' secondary education attendance adds 0.3 per cent to a country's GDP.
In fact, the recently released 2014 UN Human Development Report described educating women as 'the closest thing to a silver bullet in human development'.
And a statistic that I am sure you are familiar with, and one that was at the heart of discussions at the APEC Women and the Economy Forum which I attended in Beijing in May this year: according to the UN, limits on women's participation in the workforce across the Asia Pacific region costs the economy an estimated US $89 billion every year.
I'm glad Australia has recognised the unique challenges and opportunities facing women and girls around the world, and has made gender equality and women's empowerment a priority in its foreign policy and overseas aid program.
We're focusing our efforts on three areas where change will make a significant and lasting impact for women and girls: women's leadership (including in politics, close to my heart), women's economic empowerment, and ending violence against women.
Foreign Minister Julie Bishop has set a target requiring that at least 80 per cent of aid investments, regardless of their objectives, effectively address gender equality issues in their implementation.
In July, I saw the results of our aid investment when I hosted the Pacific Women Policy Makers Dialogue in Tonga – a program supported by Australia's ten-year, A$320 million Pacific Women Shaping Pacific Development initiative.
Less than four per cent of parliamentarians across the Pacific are women, compared to a 20 per cent global average.
Through this initiative, we are aiming to improve political, economic and social opportunities for Pacific women.
We are working with women leaders in the region and aiming to increase the numbers and effectiveness of women in decision-making roles at all levels.
At the dialogue, I once again witnessed the huge reservoir of talent and energy in our women leaders that we are so far failing to access.
I see that same talent and energy here today in the delegates to the G(irls)20.
In key respects, the G(irls)20 has much in common with the G20. You represent the G20 countries and regions, and have come together to debate and discuss the challenges and opportunities facing our world, through an economics lens.
But, I suspect that your personal stories and experiences as young women leaders are likely to be very different from those of your G20 counterparts.
That is the incredible value of a forum like the G(irls)20.
It is the value of your efforts as leaders in your own communities, which extend well beyond this event.
No country or community, regardless of its circumstances, can reach its full potential while drawing on the ideas and talent of only half its population.
This is something that the G20 economies have begun to recognise, with many countries looking at ways to increase women's workforce participation as a way to achieve economic growth.
The range of policies being considered cover: greater access to child care, women-friendly workplaces, tax concessions to help women return to the workforce, support for part-time employment and enhanced parental leave.
Australia's G20 agenda puts women at the forefront of financial inclusion, responding to the specific challenges faced by women when they access financial services and learn about financial matters. A new Women's SME Finance Hub has been created to share information on financing women owned businesses
This is welcome progress.
In this role, I often talk about 'empowerment'.
To me, empowerment is firstly to give someone the tools and information to form views on how to improve the world around them.
It's then to listen closely to what that person has to say.
My message to you is that your community needs you to be engaged in leadership and decision-making.
Your voice is welcome – it is essential – in our public life.
My message to our private sector colleagues here tonight is to look around you.
From my research into the G20, I understand that reliable energy supplies are a focus this year.
I can't think of a more promising, untapped energy source than the world's young women.
I welcome the addition of the G(irls)20 voice to the G20 conversation.
I encourage all G(irls)20 delegates to seize every opportunity to seek information, to speak up, to be a leader.
I don't think this group of young women needs to be reminded that leadership is not limited to those in formal positions of power. Leadership is a mindset: that you, and your actions, can make a difference.
A real and lasting improvement to the lives of women and girls requires us all to be leaders – within our families, with friends, in workplaces and our communities.
I know you're already stepping up to that challenge.