Kostadin Sirleshtov is Managing Partner of CMS Sofia and Head of Energy & Climate Change for Central and Eastern Europe, leading a team of more than 80 lawyers across seven CEE jurisdictions. He has over 25 years of experience in the energy sector and is recognised as one of the leading energy practitioners in Bulgaria and the wider CEE region.

His areas of expertise include conventional power, renewables, oil & gas, infrastructure, projects, PPPs, public procurement and underground resources. Kostadin previously served as Chief of Cabinet to the Bulgarian Minister of Energy and Energy Resources and has been a key figure in the development of Bulgarian energy legislation since 2000.

He has extensive experience advising energy companies, investors and project developers, including in negotiations with government authorities, state-owned energy entities and major industry participants. Kostadin and his team are consistently ranked among the leading energy practices in Bulgaria by Chambers & Partners, Legal 500 and IFLR1000.