The aim of this paper is to indicate future research likely to be most useful for government in developing the response to COVID-19 over the medium to long term. These evidence gaps and knowledge exchange opportunities were identified through the Rebuilding a Resilient Britain programme, the academic-policy engagement process hosted by the Government Office for Science (GOS) and facilitated by the Economic and Social Research Council (ESRC)/GOS Areas of Research Interest Fellows. Working Groups comprising government officials, funders and researchers discussed cross-cutting topics considered critical to the government response; assembled the evidence base, and identified gaps for future research and knowledge exchange. Nine reports were produced by these working groups, which can be found at https://www.upen.ac.uk/go_science. Who is this paper for? Funders in United Kingdom Research and Innovation (UKRI) and beyond may wish to review these identified evidence themes and gaps when planning strategic or routine investments in these areas. Funders may also wish to select proposals which are sufficiently well-specified (see those in Annex 1) for direct commissioning and/or to shape strategic investments. In addition, funders wishing to support interdisciplinary research programmes may find these useful, as all the evidence gaps and research projects described below are the result of facilitated discussions between government officials and multi-disciplinary groups of researchers. Researchers planning proposals: Researchers may wish to use this paper to develop research proposals, as the gaps identified in this paper speak directly to priorities developed through a process of co-design between policymakers, funders and researchers. Government officials: May wish to inform strategic planning around research commissioning, calls, and collaborations, and may find this paper useful when preparing future Areas of Research Interest (ARIs), or to gather ideas for their own research commissioning and activities. Teams supporting cross-departmental research initiatives or commissioning may find the proposed cross-cutting research gaps useful to scope research collaborations across government. In addition, the sections on policy dialogues represent opportunities to bring together government departments to discuss critical topics of relevance to more than one department. This paper offers an overview of the key gaps and themes identified by our Rebuilding a Resilient Britain programme, which assessed the key research priorities for government departments as identified by the Chief Scientific Advisers. In 2019, two Fellows were appointed jointly by ESRC and GOS to promote academic-policy engagement around Areas of Research Interest, which are statements of priority research areas identified by government departments. Between April-November 2020, the Fellows ran the Rebuilding a Resilient Britain programme, which sought to identify evidence relevant to sets of cross-cutting ARIs identified as critical to supporting the government response to COVID-19 in the mid- to long-term. Nine working groups brought together over 250 researchers, policy officials and funders to identify existing evidence, key messages for decision-makers arising from this evidence, and gaps in the current research evidence base. Working groups were given between 4-31 ARIs to consider. In some cases, no evidence was identified due to lack of specific expertise within the group (for a complete list of unanswered ARIs, see Annex 2). It is therefore possible that relevant evidence may be identified with a more targeted and resourced search and synthesis process. In this paper, we address the specific and higher-level evidence gaps and research ideas proposed by working groups.