He will report to Bobby Morse, senior partner and head of Buchanan Natural Resources Practice (BNRP).
Morse commented: ‘Our focus on specific sectors plays well to Charles' strengths as we continue to build on what has become the clear leader for quality growth companies in the natural resource arena. We look forward to working with Charles in consolidating our position in mining in particular, and to taking Buchanan on to its next level of development.’
O'Brien has also worked at KPMG in Dublin and ABN AMRO in Australia.
Buchanan currently advises fast growth mining companies including Centamin Egypt, Western Coal Corporation, Petra Diamonds, and Avocet Mining, through to oil and gas companies such as Hunting plc, Gulfsands Petroleum, Melrose Resources, and Nautical Petroleum.