More litigation with Russia and more openness to Western investment may emerge under Vitrenko. Interspersed with stints at Naftogaz, Vitrenko worked for Pricewaterhouse Coopers in Kyiv, Merrill Lynch in London, and Amstar Europe, a private equity fund, affiliated with a Denver group. He is CEO of AYA Capital, a Kyiv-based investment company he founded a decade ago. At Naftogaz, he worked on several large Eurobond placements.