The Rio Olympics will start the volunteer registration.

The 2016 Rio Olympics will start recruiting volunteers on 28th this month.

http://www.rio2016.com/en/get-involved/volunteers#

Acooding the website, the volunteer-related schedule is as follows;

And the types of volunteers are;

<General volunteer>
Event Services

<Specialist volunteer>
Medical Services
Technology
Sport
Transport
Language Services
Anti-doping control




I heard that the Tokyo Olympics might start hiring the volunteers next year. It's much earlier thatn the Rio. Or Rio is very slow? I have no idea though.