Ethos leads engineering consultancy across EMEA, delivering multidisciplinary excellence for ambitious projects and trusted global client partnerships.

Biography

Greg Hayden is the proud CEO of Ethos Engineering, the award-winning MEP consultancy. Ethos employs over 250 talented people headquartered in Dublin, working on some of EMEA's most exciting, challenging, and innovative projects for the built environment. Following Ethos' private equity investment from Exponent and recent acquisition of SimStudio, he continues to drive the company's ambitious growth strategy and expansion of in-house capabilities.

Under his leadership, Ethos has built its success on a people-first culture that empowers everyone to deliver their best work every day. This same philosophy extends to client relationships, where the company focuses on building long-standing partnerships rather than transactional engagements. Greg believes that by growing alongside clients and consistently raising project delivery standards, Ethos creates value that extends far beyond individual projects.

Central to this approach is his role in attracting, growing, and enabling the best people in the industry to support clients in the delivery of best-in-class projects. He is very honoured to be working with some of the most significant clients in the Data Centre, Smart Buildings, Sustainability, and Commercial Sectors. He enjoys continually learning and developing, from his Honours Degree in Energy Engineering to his International MBA, and his more recent AI, Blockchain, and current IoT business strategy training at MIT. "The more I learn, the more I realise there is so much more I do not know."

He is passionate about continually driving a culture of innovation at Ethos. He lives by the motto 'innovate or die' and works to ensure that the company constantly brings smart ideas, creativity, and 'outside the box' thinking to projects. This should not be at the cost of people's work-life balance, and he constantly drives a 'work smarter, not harder' approach with people and processes. He constantly reminds the team that everything they do is about adding value for clients, and if it's not adding value, then why are they doing it?

"I love bringing the best people together to solve problems. My mantra is that we should always aim to onboard that person who is smarter than we are. I am committed to investing in the personal development of our people and encouraging everyone to reach their full potential."

Despite the company's significant growth, Greg continues to immerse himself in the day-to-day operations of Ethos, ensuring the vision of the organisation he set out with over 20 years ago is never lost, only strengthened and improved with the people and clients who shape the company's future.

He is motivated by clients' goals and is passionate about understanding the 'why' of every project they work on. Above all, he is absolutely committed to Ethos driving innovation for a sustainable digital future whilst delivering the outstanding outcomes that define the company's reputation.

Biography
Colm Devin is a founding Executive Director of Ethos Engineering and currently serves as the company’s Chief Commercial Officer. With over 30 years of experience in the construction industry and 20 years dedicated to the vision and growth of Ethos, Colm has played a central role in shaping the company’s journey from a dynamic Irish start-up to an ambitious, people-first international consultancy.
Since Ethos was established in 2005, Colm has brought unwavering commitment, energy, and creativity to his leadership. His deep-rooted passion for the business is reflected in every aspect of his role, championing innovative, sustainable engineering solutions, nurturing a culture where employees thrive and building lasting partnerships with clients across 19 countries and growing. He has been central to delivering multiple complex projects, earning a reputation for both technical excellence and commercial clarity.
As Chief Commercial Officer, Colm leads Ethos’ commercial strategy with a sharp focus on international expansion, particularly in scaling the business into a formidable global consultancy in the Data Centre sector. His strategic mindset, paired with a strong commercial spirit, ensures the company remains agile, future-focused, and competitive in a rapidly evolving market. He is passionate about advancing Ethos’ reputation as a best-in-class consultancy for hyperscale and enterprise clients seeking high-performance, mission-critical infrastructure.
Colm’s leadership is deeply employee-centred. He believes that culture is the cornerstone of sustainable success and works tirelessly to foster a collaborative, inclusive environment where people are supported, empowered, and inspired to deliver their best. His ability to align commercial growth with team development has been fundamental to Ethos’ continued momentum.
Among his many career milestones, Colm played a lead role in securing strategic investment from Exponent, a transformative step in Ethos’ scaling ambitions that opens new opportunities for growth with renewed confidence and capability.
Whether leading high-level strategy, supporting global partnerships, or mentoring future leaders within the organisation, Colm remains deeply driven by the values that founded Ethos: ambition, trust, excellence, and people at the heart of everything.

Biography
John Coroner is Chief Operations Officer (COO) and one of three founding Executive Directors at Ethos Engineering. In his operational role, he is deeply involved in the day-to-day structuring and management of engineering teams whilst playing a key role in the company's strategic direction and growth trajectory.
As a founding director, John takes pride in what Ethos has achieved and remains passionate about driving innovation and embracing improved working methodologies that deliver significant benefits for clients. The company's growth is founded on delivering optimal solutions within precise timeframes, focusing every resource to give clients exactly what they need. John's aspiration for Ethos to be the company others in the sector look to emulate keeps him singularly focused on emerging trends and organisational adaptation.
John brings distinctive "left field thinking" to key projects, treating each as completely bespoke with no pre-ordained solutions. This approach creates significant value for both process and project outcomes. He enjoys involvement beyond mechanical and electrical solutions, participating in early strategic thinking and programme design improvements with clients. 
Recognising the importance of process innovation, John has driven the careful assessment and integration of AI tools throughout Ethos. He understands that human input is crucial to capitalising on AI system value, ensuring teams undergo extensive training to maximise their capabilities. This commitment to innovation extends to strategic talent development through upskilling existing people, strategic new hires, and working with the executive board on key acquisitions. 
In 2020, John completed an Honours Degree in Irish Law. "I love the way engineering takes client parameters or small pieces of information and uses them to find innovative bespoke solutions. Without knowing it, engineers automatically couple their education with the application of the laws and regulations in their area and use these as the rules of engagement in reaching the final solutions. The understanding of the law helps me every day in how I work as an executive director, in driving project and business decisions."
John's unique combination of engineering expertise and legal understanding, coupled with his hands-on operational approach, ensures Ethos continues to find innovative solutions whilst navigating the complex regulatory and commercial landscape of modern engineering projects.