This report discusses how the three main British political parties select their parliamentary candidates, and assesses the impact of various reforms they have introduced into their candidate selection processes in recent years.

Innovations we studied include primary elections, all-women shortlists, the Conservatives’ A-List and gender quotas, as well as moves in all parties to professionalise candidate assessment processes. We also set out a dozen recommendations for reform of candidate selection processes.

We find that strong action by party leaders is the surest way to deliver a quick win in terms of improving the diversity of MPs. However, this often comes at the expense of local party autonomy, causing conflict between party leaders and local activists.

Top-down approaches such as all-women shortlists also do little to address the underlying problem that those coming forward to become candidates are unrepresentative of the population. We therefore recommend that more effort is made to improve diversity in the “supply” of candidates, and that steps are taken to reduce barriers to those from non-traditional backgrounds, for instance through the provision of means-tested bursaries for parliamentary candidates.

We also favour the limited experiments to date with primary elections, where candidate selection processes are opened out beyond party members to the wider public, and recommend that all parties go further, using primaries for the selection of parliamentary candidates and also for city mayors. We also back the Coalition’s initial commitment to provide state funding for primary elections.