<< Background >>There is a significant social investment gap in Europe, in particular with regard to social care and support. The situation has only worsened with the impact of the COVID-19 pandemic. Many social care providers traditionally rely on public forms of investment and have more limited understanding of private investment. Similarly, private investors tend to not have a good understanding of social care and support. Universities do not have strong training programmes on social investment.<< Objectives >>The main project objective is to boost social investment in Europe by establishing a Knowledge Alliance that provides professional development opportunities to create more informed intersectoral working between investors and social care providers.<< Implementation >>By the end of the project, the a4i project has helped social care providers, private investors and higher education institutions to form a common understanding on social investment and develop training material; both online and face-to-face.<< Results >>The main results of the a4i project are - State of Play report on Social Investment, European Guidance on Social Investment- a universal professional development programme on social investment & transpositions in BE, CZ, ES; following pilots in the three countries involved- An online knowledge centre with a Massive Open Online Course (Universal & BE, CZ, ES), a list of promising practices, a mentor database and much more.