The two EU agencies that are leaving London because of Brexit are crucial for the functioning of the bloc's single market in the fields of medicines and banking.
Here are details of the regulators whose new host cities 27 member states will vote to choose on Monday:
European Medicines Agency
The EMA, based since 1995 in London's Canary Wharf business district, evaluates and supervises medicines for human and animal use.
It helps national authorities authorise the sale of drugs across the EU's single market, which currently comprises 28 countries and more than 500 million people.
The EMA employs nearly 900 people.
Because it hosts delegations and regular functions for experts, it had 36,000 visitors in 2015, including 4,000 from outside the EU, who required 30,000 nights in hotels, in a boost for the local economy.
The EMA has a 300-seat auditorium for events.
European Banking Authority
The EBA is the smaller of the two agencies up for grabs and is based just a few hundred metres from the EMA in London.
The EBA's mission is to guarantee financial stability in Europe, including the integrity, effectiveness and orderly functioning of the EU's banking sector.
It works to harmonise banking rules across EU countries.
Created in 2011, it is best known for its banking "stress tests", designed to test how well banks can withstand a possible repeat of the 2008 financial crisis.
The EBA has 169 employees, as of 2016, and its visitors generate around 9,000 nights a year in hotels. It also carries out many missions in member states -- 700 in 2016 -- which require extensive air links in the new host city.
The EBA also has two data centres in separate locations in Britain run by external contractors.