He began his career working as a corporate attorney for Winstead Sechrest & Minick, in Austin, Texas, before joining the venture capital firm of Enterprise Partners in La Jolla, California. He then joined Crosspoint Venture Partners, in Woodside, California, where he became a partner in 1999. In 2000 he formed Impact Venture Partners, a $100mm early stage venture capital firm, in New York City. Dell joined Austin Ventures as a venture partner in 2009. Dell joined Goldman Sachs as a partner in 2018.