“We must turn the greatest collective challenge facing humankind today – climate change – into the greatest opportunity for common progress towards a sustainable future.”

People everywhere look to the United States to use its remarkable power to help lift humanity up and to work for the common good.

Women must be full partners in development, so they can lift themselves and their communities out of poverty.

My observation is China is thinking more as a global player than regionally, in both politics and economics.

Only through women’s full and equal participation in all areas of public and private life can we hope to achieve the sustainable, peaceful and just society promised in the United Nations Charter.

Climate change, demographics, water, food, energy, global health, women’s empowerment – these issues are all intertwined. We cannot look at one strand in isolation. Instead, we must examine how these strands are woven together.

The unity in diversity of the United States is one of the country’s greatest strengths.

The longer we delay, the more we will pay.

Migration is an expression of the human aspiration for dignity, safety and a better future. It is part of the social fabric, part of our very make-up as a human family

Reason doesn’t mean very much in a country like North Korea.

With her courage and determination, Malala has shown what terrorists fear most: a girl with a book.

I am willing to take any measures when it comes to the fundamental principle of human rights.

In a world of plenty, no one, not a single person, should go hungry. But almost 1 billion still do not have enough to eat. I want to see an end to hunger everywhere within my lifetime.

Many say our world is at a tipping point. If we do not act together, if we do not act responsibly, if we do not act now, we risk slipping into a cycle of poverty, degradation, and despair.

I believe in a world of justice and human rights for all. A world where girls can grow up free of fear of abuse. A world where women are treated with the respect and dignity that is their right. A world where poverty is not acceptable. My dear young friends, you can make this your world.

World military spending has now risen to over $1.2 trillion. This incredible sum represents 2.5 per cent of GDP (global gross domestic product). Even if 1 per cent of it were redirected towards development, the world would be much closer to achieving the Millennium Development Goals.

A deal must include an equitable global governance structure. All countries must have a voice in how resources are deployed and managed.

The most complex challenge for an actor is the ability to give dimension to the story from the time that it happened, not from the present.

Academic freedom is being lost by a great many people who dare to challenge Darwinism. That’s a terrifying situation. That’s contrary to the principles of science.

I’m a total luddite when it comes to technology. Pretending I know how to use a computer is a challenge.

Sometimes our body is willing, but our mind is weak. Sometimes our mind is willing, but our body is weak. Do not be afraid. Strive to extend your capacity but do not be disappointed with yourself. What does not challenge us, cannot change us.

Some people are quick to challenge others but refuse to look in the mirror and challenge themselves.

She (a woman politician) will be challenging a system that is still wedded to militarism and that saves billions of dollars a year by underpaying women and using them as a reserve cheap labor supply

I am confident that we will meet whatever challenges the future may bring.

As a company grows, communication becomes its biggest challenge.