Previously, Polese served as CEO of SpikeSource Inc., which developed software to automate open source application management. The company was incubated in 2003 at VC firm Kleiner Perkins Caufield & Byers and launched its first products in April 2005. The company was acquired by software company Black Duck in November 2010. Prior to SpikeSource, Polese co-founded Marimba Inc., an Internet-based software management pioneer. She served as President and CEO until 2000, leading Marimba to profitability. She was Chairman from 2000 - 2004, when Marimba was sold to BMC for $239M.