BDO in Ireland appoints engineering specialist Mark O’Sullivan as new Partner of Research & Development Incentives practice

Mark O’Sullivan becomes Ireland’s first dedicated R&D Partner with primary science and technology qualifications. 

BDO is delighted to announce the appointment of Mark O’Sullivan as the new partner for its Research & Development (“R&D”) Incentives practice. This announcement marks the first appointment of a dedicated R&D Incentives partner with primary science and technology qualifications in Ireland.

Mark specialises in securing R&D funding for companies through government grants and tax incentives, including RD&I grants, R&D tax credits, and the Knowledge Development Box (“KDB”) regime

Mark’s technical background, coupled with his tax advisory expertise, positions him as one of the leading R&D Incentive advisors in Ireland. This unique knowledge-base enables him to offer strategic and informed advice on the specific technicalities of these R&D Incentives, whilst also successfully managing its tax and financial elements. Since joining BDO, he has been involved in the successful qualification of over €500 million of expenditure for R&D tax credits and grant funding and has been involved in many of the largest R&D tax credit claims ever made in Ireland. 

As partner, Mark will lead BDO in Ireland’s R&D Incentives practice - Ireland’s largest engineering led practice and one of the most successful and widely regarded in the country. The practice is one of the most experienced in Ireland, combining engineering and scientific experts with taxation professionals offering clients a unique, robust and highly efficient, end-to-end service.  

Mark is a member of Engineers Ireland and holds professional qualifications in Mechanical Engineering, Manufacturing & Design Engineering, Medical Physics and Computing. He is also a qualified Chartered Tax Advisor and has a significant amount of Revenue audit experience.  

Speaking on the appointment, BDO Managing Partner Michael Costello said:

“I am delighted to announce the appointment of Mark O’Sullivan as partner to our R&D Incentives practice. Promoting from within and attracting professionals with diverse educational and professional backgrounds is a key element of our business strategy. It ensures that we have the right blend of expertise and are always looking for new ways to add value for our clients. 

At a time when the business environment is facing complex health and trading issues, we continue to expand our service offering to meet the needs of our clients. The team has done tremendous work growing the R&D Incentives practice into one of the best in Ireland and with Mark’s unique expertise at the helm, I am confident that we will continue to strengthen our offering in this area.” 

Speaking on his appointment, Mark O’Sullivan said: 

“I am very pleased to be joining the BDO Partnership and keen to build on the strong market position that we have successfully established in the R&D Incentives sector. It’s an exciting time for R&D in Ireland as the number of organisations engaging with our national R&D Incentive schemes continues to rise and the pace of change in science and technology continues to grow. The market is presenting increased opportunity for organisations seeking to avail of R&D Incentives and I look forward to working with our team of engineers, scientists and tax experts to help maximise those opportunities."

For more information, or to find out more about BDO Ireland's Research & Development Incentives practice, please contact Mark O'Sullivan at or 01 470 0113.

Subscribe to receive the latest BDO News and Insights

Please fill out the following form to access the download.