In scientific funding, as in agriculture, monoculture is risky. However well-meaning and diligent its paymasters may be, a field that has only one source of funding runs the risk of missing opportunities and succumbing to a shared perception of what is possible and what is not. Diversity is thus to be prized. The current increase in scientific funding from individual philanthropists, private foundations and non-profit organizations, particularly in biomedical science (see page 248 and http://www.nature.com/news/specials/philanthropy), is a welcome development in a field that is largely dominated by governments.

With this new money come new attitudes. Philanthropists tend to have strong and clear ideas about what should be funded. If, as many of the new wave did, they made their money in industries that are themselves driven by research, they will often want to delve deeper into what scientists are actually doing than the foundations of yesteryear, either out of pure intellectual engagement or a desire to micromanage.

Philanthropic organizations tend to be interested in particular outcomes, rather than in simply funding the most academically interesting question that presents itself. They may take a more business-like approach, too, demanding milestones and results. And they can show a greater readiness to turn off the funding if these things are not forthcoming — or, in some cases, simply if the stock market takes a tumble.

The mixture of risk tolerance and accountability seen in some foundations, particularly those concerned with a specific disease, may seem contradictory, but it need not be so. What matters to the administrators who dole out the cash is normally not success per se, but demonstrated diligence in following the risky strategy set down. This level of accountability can make some researchers uncomfortable (see page 252). If basic researchers expect to benefit from these disease-focused foundations, they need to make a compelling case that their studies offer a real chance of progress towards a cure, and to document the way those chances play out.

This does not mean that the donor is always right, however. There are real risks that some areas of biomedical research could be dominated by a few rich people and the boards on which they sit, with little guidance from scientific consensus or expertise. Philanthropic groups need to think carefully about how best to award money, and to realize that no single strategy will succeed in every case. What's right for Huntington's disease, where a faulty gene has been named and shamed, may be wrong or premature for something more complex, such as autism. Rushing into the wrong strategy will merely waste time and money.

In the end, though, it is the philanthropists' money to waste. They would obviously be wise to make sure that the money is well spent, but they cannot always be stopped from other courses. Rather, it is for the scientists who stand to benefit from such largesse to ask themselves whether the money on offer is worth the risks of the course being prescribed. By doing so, and by helping donors identify the most pressing scientific questions relevant to their remit, the scientific community can help make the most of the new diversity offered by the philanthropy boom.