The aim of this study is to develop a sustainable business model for a Third Sector Organisation (TSO) in order to be self reliant and achieve business excellence. This study was carried out through extensive literature review, a comprehensive case study which is supplemented by analysing the case TSO’s internal documents, discussions and interviews with its core staff. The study proposes a mixed business model which is driven by both social and economic values. Three strands of ‘convergence business ideas’ were suggested and twelve factors toolbox was developed. This study supports the need for reform in TSOs funding portfolios, government support in TSO’s capacity building in order for the TSOs to be able to actualise the transformation and need for diversification and internationalisation of their existing services.