A group called Taxi Drivers for Change has organised the day of action, which saw services stopped from 4am this morning.
Drivers are calling for the suspension of new licences and a review of the taxi industry.
Pickets will be placed at ranks across the country.
Taxi drivers in Waterford city are taking part in a protest from noon until 3pm.
Traffic disruption can be expected in parts of the city during this period.
A number of copies of the recent report into the industry by Goodbody have been burned by protesting taxi drivers.
Spokesperson for the group Frank Byrne said: 'It is encouraging to see increased numbers of taxi drivers and other organisations now participating in the campaign. The numbers are growing all the time.'
Meanwhile, around 20 taxis took part in a four-hour work stoppage at Dublin Airport this morning.
The protest, from 7am to 11am, was organised by SIPTU.
