Comparing Theory & Practice in Social Finance - Impact Measurement in Ireland Chiara Pellegrini Scuola Superiore Sant’Anna, Institute of Management, Pisa, Italy chiara.pellegrini.tn@gmail.com A case study was undertaken in Ireland to examine how different providers of social fi-nance in Dublin performed ex ante and ex post evaluations of their investments. A brief overview of social finance is provided, introducing basic terminology and highlighting strengths and challenges related to this emergent field. In particular, the section pre-sents the literature examined to assess the state of theory - and to some extent of practice - in relation to the emergence and assessment of social finance and impact in-vesting in different regions including Europe, the United States, Canada and Australia. This section discusses that there appears to be two ‘patterns’ of impact assessment (IA) emerging. One is more focused on measuring the results (outputs, outcomes, impact) across the three (or more) dimensions of the ‘Triple Bottom Line’. This approach is more apparent when large philanthropies and impact investors are driving the devel-opment of IA. Ratings approaches to IA also tend to be more prevalent in these cir-cumstances, allowing the assessment of ‘portfolios’ of initiatives and investments. The second pattern is more focused on processes and applying different measures in dif-ferent situations following a ‘Theory of Change’ logic. More nuanced Social Return ap-proaches to IA allow for both outcomes and processes to be evaluated, although in the UK there does appear to be a coalescing around Social Return on Investment (SROI) as the preferred institutional option for measuring impact. This approach is more apparent in contexts in which government and/or networks of third sector organizations are driv-ing the IA agenda. In either case, there are still many debatable assumptions, risks, challenges and issues identified by theorists and practitioners. The second part of the study explores approaches undertaken to evaluate social finance providers in Dublin. In particular, it describe the types of social finance providers currently operating in Dublin and analyses how they are (or are not) engaging with current 'state-of-the-art' evalua-tion of their investments.