If there are three or more candidates, Tory AMs choose the top two but the final choice is left to party members.
The Conservatives' Welsh Board has set the following timetable:
Nomination papers issued: 29 June.
Close of Nominations: 16 July.
Nominations announced: 17 July.
Ballot of Tory AMs if there are three or more nominations 24 July.
Hustings for top two candidates: 30 July to 10 August.
Ballot papers posted to all party members in Wales: 15 August.
Deadline for return of postal ballots: 5 September)
Count and Declaration 6 September
The Conservatives expect to have a new leader in place before Welsh Labour has decided on the rules for choosing Carwyn Jones' successor.
They may not even have to wait until September, if only one AM gets the required nominations from at least three members of the Tory group.
On behalf of the whole Welsh Conservative party I would like to take this opportunity to thank Andrew RT Davies for the exhaustive effort and energy he put into the post of group leader in the assembly. It is now vitally important that we build on that hard work by getting a new leader in place without delay. The work doesn’t stop, and I look forward to joining forces with whoever is chosen to take the Welsh Conservatives forward as the party that is the only real credible alternative to Welsh Labour.