Over the last three decades, policy-makers have developed numerous measures, policies, projects and programs with the intention to increase the enrolment and participation of underrepresented groups, however, little is known about the ways in which such initiatives shape opportunities for potential students. Knowing which of these initiatives work and whether they are achieving their intended goals is of utmost importance for policy-makers across Europe. This paper aims to collect, document, scrutinize and critically analyze the current research literature which assesses the effectiveness of different public initiatives at Higher Education Institutions’ (HEIs) level for widening access for underrepresented groups and, at the same time, to identify gaps and make recommendations for potential further research. The 17 identified studies can be categorized based on the access measures they analyze: (1) outreach, counselling and mentoring of prospective students; (2) financial aid measures, and (3) preparatory courses and programs. The findings show that there are little research and information about the actual outcomes of most measures to increase access to HE. We found a lack of adequate, reliable and consistently collected data about the policy instruments already put to practice. Since there is no excuse for the lack of effective action towards more equitable educational systems, more evidence-based approaches will be necessary to learn from these specific access measures and move forward towards more efficient equity policies.