Sienna Ventures, founded in 1990, is a venture capital firm based in California that specializes in early-stage technology investments. They primarily invest in companies in the software, medical technology, wireless communications, and Internet infrastructure sectors. Sienna Ventures provides funding between $5 million and $25 million to start-up businesses and also partners with other investors to provide growth capital for mid-sized companies. They take an active role in their investments, working closely with the management teams and offering support in areas such as business alliances, recruiting, and strategy.