Leadership Team

The Institute of Sustainability Studies was founded, and is led, by passionate professionals who are highly experienced in both sustainability issues and education delivery.

The leadership team understands what it takes to create and deliver world-class education products. We are educators, entrepreneurs, strategists, and creatives united by our mission to simplify and democratise sustainability education.

Justin Cullen

Executive Chairman

Justin is an experienced business leader with a specialisation in driving transformative changes. Having pioneered the domain of digital transformation since the mid-1990s, Justin has recently shifted his focus to sustainability and circularity.

He also chairs Junk Kouture, a global platform promoting creativity and sustainability among youth, with participation from over 100,000 individuals across 35 countries, amplifying its impact on the next generation.

Niall Collins

Chief Operating Officer

Niall is a committed sustainability professional and climate practitioner with a Masters in Sustainable Energy and Green Technology. He also holds advisory roles within Sway, Clearstream Solutions and KPMG Sustainable Futures.

Niall has helped a range of businesses with their sustainability strategic plans and implementation processes and ongoing development.

Shruthi Prakash

Marketing Manager

Shruthi is a dedicated digital marketer whose passion for all things digital drives her to leverage her skills to design campaigns that resonate with audiences and drive meaningful engagement, with a people-first marketing approach.

Committed to eco-conscious living, she reduces her carbon footprint through mindful resource use, inspiring others to embrace sustainable choices.

Nazia Naheed Husain

Product Manager

With a strong background in environmental policy, Nazia is dedicated to driving sustainability and fostering partnerships for a brighter and greener future. She actively engages in crafting pivotal policy submissions directed to the European Commission as a member of the Zero Waste Alliance of Ireland.

She supports upcycling initiatives and is an advocate for ‘reduction’ over ‘recycling’ and ‘reuse’.

tom buttery

Tom Buttery

Corporate Education Advisor

Tom is a sustainability professional with a background in corporate sustainability partnerships, as well as experience with a not-for-profit edtech initiative.

He has set up reforestation partnerships with well-known companies across a broad range of industries, and is now eager to help many others to kickstart a more holistic sustainability journey.

richie denieffe

Richie Denieffe

Course Advisor

With a background in Design Thinking for Sustainability, Richie is an innovative problem-solver, adept at interpersonal communication.

Committed to advancing sustainability through education, he is now eager to provide effective guidance to both individuals and organisations on their sustainability learning journeys.

Alex comerford

Alex Comerford

Operations Manager

With years of engineering experience in the construction sector, Alex pivoted his career focus towards sustainability, earning a master’s degree in Finance and Renewable Energy.

A strong advocate for sustainable business practices across various industries, he is dedicated to promoting and practising an environmentally responsible lifestyle.


Christian Iheacho

Frontend Developer | Technical Integration Manager

Experienced Frontend Developer and Technical Integration specialist with a solid background in HTML, CSS, Tailwind CSS, JavaScript, Typescript, React and WordPress. Over 5 years of expertise in frontend development, complemented by a master’s degree in Computing from Griffith College Dublin.

Proven track record in designing and executing API integration strategies, ensuring flawless communication between diverse systems. Eager to contribute technical excellence and integration skills to drive impactful solutions.