Having covered social entrepreneurship for Forbes for nearly six years, one of the biggest issues I see in the community of changemakers is limited vision. The world’s most pressing problems—poverty, disease and climate change—are massive are require solutions that scale. It is time for social entrepreneurs to stop thinking small.

Most of the world’s population can’t afford to own a car. Current estimates are that there are just over a billion cars on the road. Even if we assume that most are owned by one car families and that many people who can afford a car don’t own one, we can quickly conclude that five billion people lack the economic resources even to own a Tata Nano.

While it is true that most of these five billion people have adequate food, water and shelter, they are not enjoying a lifestyle that most people in the developed world take for granted. And nearly a billion people in the world are living on less than $2 per day, aren’t sure where their next meal is coming from and/or lack access to safe, clean drinking water. More than two billion people lack a sanitary place to defecate.

The world’s problems are huge. Stop thinking small. Your project or enterprise can scale or be replicated.

Today, there are at least 65 million girls who are not in school. Ann Cotton was a graduate student in Cambridge doing research into the problem in 1991. She is one of the most inspiring changemakers I’ve interviewed over the past six years (among more than 900 people). She founded CAMFED, the Campaign for Female Education. She got her start visiting Zimbabwe where she had learned boys outnumbered girls in school by a ration of 7:1. She was repeatedly told that parents simply didn’t want their girls educated.

When she started talking to parents she found that they did want to educate their girls but couldn’t afford to have all their kids in school and so sent their boys and typically kept their girls at home. Starting with a bake sale to send 32 girls to school. It worked. Ann could have congratulated herself for helping 32 girls get an education and proving that they could and should be educated but she didn’t stop. She saw that effort as a pilot program, a case study, a proof of concept to be replicated. To date, CAMFED reports having provided 249,378 girls with scholarships and having supported schools in five countries that have been attended by millions of boys and girls.

Big problems represent huge opportunities.

Narayana Health is a cardiac health care provider in India. With almost 16,000 employees, 50 facilities and 6,888 beds, the system generated about $318 million in revenue last year—its first year as a public company. Founder Dr. Devi Shetty says, “If a solution is not affordable, it is not a solution.”(See my interview with him here.) By focusing relentlessly on cost, Narayana Health has made quality cardiac care accessible to hundreds of millions of people for whom it was not available when Dr. Shetty launched the enterprise 30 years The United Nations’ Sustainable Development Goals target the elimination of extreme poverty by 2030. This represents both a challenge and an opportunity for social entrepreneurs who see opportunities in selling clean water, distributed clean energy, financial services, improved nutrition and improved farming techniques at affordable prices to the billions of people who want them.

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