I am going to a business conference this week, which seems a bit crazy, but we're trying to get back to normalish.
To get in you have to have a negative test in the morning that is recorded and confirmed by NHS app.
Vaccine passports won't stop the spread, only stopping infected people mixing with non-infected people will do that.
But it is a good move all the same, as you want to encourage people to get vaccinated to help beat the virus into submission. Vaccinated people can catch it, but young and healthy ones will kill the virus before it takes holds, so isn't spread further.