Robert was educated at The Queen's University, Belfast where he came third in his year. After graduating from Queen's he completed his apprenticeship at L'Estrange and Brett.

Robert took the decision to set up his own practice and founded Robert G Sinclair & Co in 1983. Robert has acted for leading corporate and commercial clients and is well known in this field of work. He has acted in many high profile cases in these areas including tax cases, VAT cases, fraud cases and restructuring of major companies. Robert has acted for many major banks who have set up in Northern Ireland.  He has drafted much of the security documentation used by major lenders and continues to review these.

Robert has a specific interest in health matters and advises private clinics in relation to the various legal issues which may arise in the day-to-day operation.

Robert has been involved in advising companies and lenders involved in administrations, receiverships and liquidations and schemes of arrangement. Robert holds a practising certificate also in England & Wales and practises in both jurisdictions.  He has been appointed to the advisory board of several leading companies by the government.  Robert has also been appointed by the Northern Ireland Department of Education as a governor of Our Lady of St Patrick's Grammar School, Knock.      

Robert is well known in national hunt horse racing circles. He has owned a number of Cheltenham festival winners and winners of national hunt races in Ireland.  He is a keen runner having completed events such as the New York Marathon and is a member of several golf clubs including the K-Club, Helen's Bay where he has been Vice-Captain, Clandeboye, Aloha (Marbella) and Dunham Forest (Cheshire). As Managing Partner in the firm for over 20 years he oversees each specialist department.

With his vast commercial and legal experience and as a Queen's Law Graduate, Robert was delighted to be appointed to the Queen's University Foundation Board where he helps advance the strategic goals and objectives of the University. He is currently actively involved in the second fund raising campaign for the University and has been appointed to the committee of Health Sciences as led by Professor Paddy Johnston. Professor Johnston has spearheaded the centre for Cancer Research and Cell Biology which was supported by the Queen's Foundation Board.  Robert has run charity events for cancer research and has raised substantial sums for charity.