There are more funding opportunities for entrepreneurial US scientists than Steve Blank conveys (Nature 477, 133; 2011). These are especially pertinent in a year when the National Science Foundation (NSF) is seeking congressional reauthorization for its Small Business Innovation Research (SBIR) Program.

Although the NSF's US$5-million Innovation Corps (I-Corps) initiative is welcome, the SBIR Program has available funds of about $150 million a year. Overall, SBIR programmes at the NSF, NASA and the US government departments of energy, defence and commerce provide $2 billion in funding a year. Since their inception in 1982, they have enabled a whole generation of scientists to become entrepreneurs.

The I-Corps sends funding directly to universities rather than to small businesses. However, many SBIR-funded small businesses were originally university spin-offs, and the complementary Small Business Technology Transfer (STTR) programme already targets partnerships between universities and small businesses.

Probably the most innovative element of the I-Corps programme is its partial funding by private foundations. If this could be increased, it would help to alleviate pressure on federal funding of the SBIR and STTR programmes.

SBIR funding was significant to the success of both of the science–entrepreneurial spin-offs in which I was involved after leaving Harvard University (see http://www.aer.com and http://www.cri-inc.com). These companies have since gone public, having generated products for worldwide use in applications ranging from biomedical imaging to environmental control.