Boris Johnson and Jeremy Hunt will battle it out to become the next Prime Minister, taking part in 16 hustings events across England, Scotland and Wales.
Starting in Birmingham on Saturday, the pair will pitch their leadership plans before taking questions from audience members.
The Conservatives said there had been 20,000 applications for places at the 16 members' hustings around the country.
Party Chairman Brandon Lewis said he was “delighted with the strong interest in our hustings to date.”
Mr Hunt said he believes he can cause an upset by defeating Mr Johnson in the battle for Number 10 after narrowly securing his place in the final stage of the contest.
The Foreign Secretary beat Michael Gove by just two votes to secure his place on the ballot paper alongside clear favourite Mr Johnson, who received 160 votes.
Here are some of the upcoming key events ahead of the new leader being chosen.
Saturday June 22
The first hustings for members, organised by Conservative Campaign Headquarters, will take place in Birmingham, hosted by broadcaster Iain Dale.
Mr Johnson and Mr Hunt will each make a short pitch to the audience, followed by questions from Mr Dale and the Tory members at the event.
June/July
There will be a total of 16 hustings starting with the Birmingham event.
They include a "digital hustings" on June 26, with a series of events across England, and one each in Scotland and Wales.
July 6-8
Conservative members should receive their postal ballots.
Week commencing July 22
A new leader will be announced following the ballot of 160,000 Conservative members.
Prime Minister Theresa May will then see the Queen to formally resign and the new leader will be invited to Buckingham Palace to form a government.
