General rule: most people pick the default option if there is one. For example, organ donation [1]: Germany and Austria are culturally very similar, but in Germ

General rule: most people pick the default option if there is one. For example, organ donation [1]: Germany and Austria are culturally very similar, but in Germany 12% of citizens are organ donors and in Austria 99%. The reason: Germany is opt-in, Austria is opt-out. The interesting thing about GDPR is it officially bans "opt out" tracking cookies - you need someone's consent, although lots of sites interpret that in a way which ... let's just say if they applied the same standards of consent to their private lives they'd very quickly find themselves at the center of the next #MeToo campaign. GDPR does allow you to make the "Yes" and "No" buttons the same size, so "equal choice" rather than "opt in" - maybe that gets you better conversion rates? [1] http://www.behaviouraldesign.com/2015/08/11/why-99-of-austrians-donate-their-organs/ http://www.behaviouraldesign.com/2015/08/11/why-99-of-austri...