Rimkus appoints Mark Hollis as director in global energy services team
Rimkus has appointed a new director in its global energy services wing. Mark Hollis brings more than three decades of experience to the role.
Global engineering and technical consulting firm Rimkus has named Mark Hollis as director in its global energy services team, further strengthening its ability to support clients in resolving complex technical disputes, major claims, and contractual failures across the global energy and infrastructure sectors.
Hollis commented, "I am excited to join Rimkus and to bring more than three decades of energy engineering experience to its forensic and dispute-resolution practice. I look forward to helping clients get to the root cause of complex failures and to resolving disputes – including delay and quantum – across oil and gas, industrial decarbonisation, clean fuels and energy storage.
Hollis brings more than 32 years of international experience in the oil and gas and wider energy sectors. A Chartered Chemical Engineer with an Executive MBA, his background spans both operator and senior consulting roles, leading complex, large-scale developments across upstream, midstream, and downstream oil and gas; both offshore and onshore, across brownfield and greenfield environments, as well as the energy transition, including carbon capture (CCUS), hydrogen, sustainable aviation fuel (SAF), and long-duration energy storage (LDES).
Throughout his career, he has delivered multidisciplinary engineering and project leadership on major global energy infrastructure projects. He has advised operators, national oil companies, governments, and investors across the full project lifecycle; from feasibility and concept selection, through Pre-FEED and FEED, to construction, commissioning, and operations. His experience spans the UK, Europe, the Middle East, Africa, Asia-Pacific, and North America, with particular strengths in brownfield integration, techno-economic due diligence, and the evaluation and scale-up of emerging energy technologies.
At Rimkus, Hollis will provide strategic project advice and expert technical services in forensic root-cause analysis of failures and delays, and the quantification of damages in complex arbitration and litigation matters, drawing on his deep facilities, process engineering design and project planning and delivery expertise, brownfield integration of complex modifications, and hands-on experience in commissioning, operations, maintenance, and performance evaluation.
“I am delighted to welcome Mark to the global energy team,” added Rod Rennisson, senior vice president for global energy services at Rimkus. “His appointment extends our forensic and dispute-resolution expertise into the energy sector in the EMEA region, building on the strong quantum and dispute capability we already have in region. Mark’s depth of engineering and operational experience across oil, gas and the energy transition will be a real asset to clients in the legal, insurance and investment communities."
Energy capabilities
As demand for energy infrastructure continues to grow and projects become increasingly complex, Rimkus is working to help clients navigate risk, resolve disputes efficiently, and protect value across major projects and investments.
According to a release accompanying the appointment, Hollis strengthens Rimkus’ expert services and dispute resolution offering within the energy sector, “enhancing the firm’s ability to support clients involved in technically complex and high-value projects.”
By combining technical expertise with commercial understanding, Hollis will work to help clients establish causation, quantify impacts, and support their position in arbitration, litigation, and insurance claims. His experience across the full project lifecycle also enables clients to identify and manage technical, commercial, and contractual risks before they escalate into formal disputes.
A Rimkus spokesperson added, “Mark brings an exceptional combination of technical expertise, commercial awareness, and global project experience. His ability to analyse complex issues and deliver clear, defensible conclusions will further strengthen our support for clients facing significant claims, disputes, and operational challenges across the energy sector.”
