In contrast to the disappointing turnouts for the Olympics last month, Paralympic organisers say they are confident of sellout crowds.
And they are predicting, for the first time, a cumulative global audience of 4 billion people.
Over 4,300 athletes from more than 170 countries are competing at the Rio Paralympics.
There are more than 500 medal events in 22 different sports, with canoeing and the triathlon included for the first time.
Paralympic competitors have either physical, visual or intellectual impairments.
They are separated into classes based on the level of their disability so their impairment has less of an impact on the outcomes of competition.
Australia's flag-bearer at the opening ceremony, men's wheelchair-basketball captain Brad Ness, has told the ABC he has taken great honour in being named to lead the team.
"I'd thought I'd experienced every bit of emotion that the Games can bring, you know, from winning finals to losing them, and not getting to the finals. But this is something completely different and something I'll remember for the rest of my life."
Brazilian Paralympic weightlifter Bruno Pinheiro has spent years preparing for the Games.
He says he hopes to inspire others with physical and mental disabilities.
And their families.
"I hope these Games bring visibility to the Paralympics movement, to motivate people who have children with disabilities or who have disabilities themselves to find sports as a means to social inclusion, as a means for a person with a disability -- so, someone who is often excluded or rejected or whose family is often embarrassed about them -- to be a source of pride for society."
With a host of new broadcasters since the last Games four years ago, the Paralympics will be beamed to a record 154 countries.
That is up almost 40 from the London Games.
But the officer for the United Nations Convention for the Rights of Persons with Disabilities laments the lack of media attention given to the Paralympics compared with the Olympics.
Guozhong Zhang, formerly with the Chinese National Paralympic Committee, has told UN Radio all athletes deserve recognition and wide media coverage.
"Paralympian sports, they need to be mainstreamed. Also, they should do more awareness-raising, to educate the people. Educate students in university and schools so that they love these Paralympic sports and (will) be part of this movement and attract the attention and support of the public, including companies, to enhance the capacity, you know, to deliver services to these athletes."
Russia is missing from the line-up.
The International Olympic Committee banned its entire Paralympic team from taking part as punishment for state-sponsored doping.
In a video, some of the Russian para-athletes say the Games will be worse off without them.
But organisers do not seem worried.
With over half of the tickets sold before the opening ceremony, they say they are confident all 2.5 million will be sold and the Games will play out before packed venues.
