Former President Donald Trump and Vice President Kamala Harris will meet for their first debate on Tuesday at Philadelphia’s National Constitution Center in a showdown that could define the rest of the presidential campaign.

The debate, which begins at 9 p.m. ET, is being hosted by ABC News. There will be no live audience and no opening statements, according to rules the network released last week. The two candidates will have under two minutes to deliver closing statements. 

Here are the debate rules:

• The debate will last 90 minutes with two commercial breaks.
• Each candidate has:
• Two minutes to answer questions.
• Two minutes for rebuttals.
• An additional minute for follow-ups and clarifications.
• Microphones will remain muted when a candidate is not speaking.
• A coin flip determined podium placement and the order of closing statements:
• Trump won and chose to deliver the final closing statement.
• Harris selected the position on the right, or stage left.
• Candidates must stand behind their lecterns for the entire debate.
• Candidates are not allowed to bring prewritten notes or props on stage.
• Candidates will not receive topics or questions in advance.