Since first launching in the United Kingdom 10 years ago, social impact bonds have piqued curiosity and debate around the world. Championed by high-profile advocates and denounced by impassioned critics, the conversation has often been wrapped in hype and misinformation from both sides.

Often called a “pay for success” model, social impact bonds usually involve a partnership between a government and private investors. The latter will fund a social program, and the government will then pay them back according to its outcomes. If successful, the investors’ risk is rewarded with returns.

In 2016, Heart & Stroke launched Canada’s first health social impact bond. In partnership with the MaRS Centre for Impact Investing and the Public Health Agency of Canada (PHAC), the foundation is testing an intervention to reduce hypertension, which can cause strokes and heart