Massive and expensive, most wind and sun-powered innovations have not found a cost-effective way to penetrate those markets.

FORBES: Social Enterprise Spotlight: Portable Solar Lighting

Because while the drug was taken off the market in the early 1960s as a cure for nausea, it was not long before researchers found it was remarkably effective in treating other conditions.

BBC: Thalidomide: a curse and a blessing?

The pine beetle is a well-known pest, not an exotic import, but no effective means has been found to stop it.

ECONOMIST: Pining for a cold winter

An audit has found that EU-funded energy efficiency projects are not cost-effective in EU member states.

BBC: EU auditors criticise energy efficiency projects

We know that the most effective models for creating lasting change can be found not in Washington DC, but in communities across the country where entrepreneurs and innovators try new approaches, then evaluate and improve them based on outcomes.

WHITEHOUSE: The Social Innovation Fund Adds Four New Intermediaries to its Portfolio | The White House

Pfizer found that a drug designed to harness the immune system to fight cancer was not effective in treating non-small-cell lung cancer.

FORBES: Magazine Article

Cold-calling seniors, swindlers have found, is an effective way to reach them because they answer the phone and will not immediately hang up on them.

FORBES: How You Can Become a Better Cop Against Elder Fraud

While we have not found evidence to support any claims, Keith exercised poor judgment that ultimately undermined his ability to remain an effective leader at Square.

FORBES: Square COO Rabois Resigns Amid Sexual Harassment Charge