The United States is the world's leading biomedical innovator thanks to a dynamic and highly productive medical research ecosystem that includes universities, government and business. One of the engines of this ecosystem has been private investment from venture capital, private equity and other sources, which has helped build new companies that have brought new treatments and life-saving medicines to patients. In recent years, investment in this sector has slowed, due to decreased risk-taking, regulatory hurdles and other issues. Nonetheless, opportunities remain, particularly for promising, innovative research coming from biotechnology companies. What can be done to revitalize private biomedical investment? Where do opportunities lie in the coming years?