John Leahy joined JSM in April 2021, bringing an outstanding track record of value creation in private equity that is directly relevant to JSM’s growth journey. He has extensive experience scaling businesses organically and through buy-and-build strategies, upgrading capabilities and operations across multiple sectors.

As Chairman, John provides strategic guidance across finance, business development and operations. He served as Operating Partner at Doughty Hanson for 18 years and has deep expertise in renewable energy, including 12 years as Chairman of LM Windpower and his current role at GEV Windpower.

Michael Booth joined JSM in February 2025 as Chief Financial Officer before being appointed Chief Executive Officer in September 2025.

An accomplished executive, Michael brings extensive expertise in financial reporting, audit, compliance, treasury management and change management. He has successfully led major acquisitions, divestments and ERP transformation programmes, combining a strategic outlook with a continuous improvement mindset. Known for building strong relationships across teams, Michael is focused on driving sustainable growth and operational efficiency, bringing both the financial rigour and leadership presence that JSM needs at this exciting stage of its development.

As co-founder and Chief Operations Officer, John Scanlon is responsible for the implementation of JSM’s strategy and the operational performance of the business. With decades of industry experience, John brings in-depth knowledge of programming, planning and monitoring work programmes, delivering proactive solutions to complex engineering challenges with safety and quality at the forefront. He provides the strategic direction to the operations that underpin the entire JSM service offering.

John is passionate about developing people from within, a commitment reflected in the establishment of the JSM Training Centre.

Helen Stewart joined JSM in January 2025, bringing more than 20 years of global HR leadership experience and a chartered professional qualification.

A transformation specialist with diverse sector expertise, Helen is skilled at translating people strategy into tangible commercial outcomes. In her role, she is responsible for building an engaged workforce, strengthening organisational capability and shaping a future-ready culture that supports JSM’s growth ambitions. Helen combines strategic thinking with a practical, human-centred approach, ensuring that JSM’s people are equipped, motivated and ready for what comes next.

David Rough leads JSM’s Power business, overseeing the design, construction and maintenance of electricity networks for transmission and distribution operators.

With over 30 years of electricity industry experience, Dave began his career as an apprentice before rising to Senior Manager level at London Electricity (now UK Power Networks), working on landmark projects including Canary Wharf and King’s Cross. He leads a highly skilled team delivering electrical engineering, project management and commercial expertise in a specialist market. Dave is driven by a genuine commitment to customer service, quality and safety in every project JSM delivers.

As Power Managing Director, Martyn plays a vital role in the growth of JSM within the Power sector.

Martyn spent nearly 25 years at UK Power Networks, with his last role, before joining JSM, being the Head of Competition in Connections. Given his industry knowledge and experience Martyn is able to provide our customers with valuable insight into getting a connection to the electricity distribution and transmission networks.

Peter Östlund joined JSM in 2025 as Managing Director – Europe and is responsible for establishing and driving JSM expansion in the EU. Peter has successfully managed major telecommunications and energy projects in Europe, particularly in Scandinavia and Germany, with a project volume of over €2 billion. His many years of experience in these regions have made him sensitive to the cultural differences that can significantly influence project success.

Peter’s combination of operational implementation expertise and intercultural competence makes him a key driver of JSM’s European development.

With more than 20 years of experience in the power and energy sector, Somansh has held senior leadership roles with Siemens T&D, AREVA T&D and British Power International. He has delivered major transmission, distribution, rail and data centre infrastructure projects, developing deep expertise across the energy and infrastructure sectors. As Managing Director for India, Somansh leads regional growth, operational performance and project delivery. Working closely with customers, partners and leadership teams, he strengthens organisational capability, governance and talent development, supporting JSM’s expansion in India and reinforcing its reputation as a trusted partner in delivering critical infrastructure for the energy transition. His professional journey across the UK and India has given him valuable international exposure, enabling him to bring a global perspective to project execution and stakeholder engagement.