It is required by law to dog Microchip and Register your dog

SIT UP and OBEY is what we teach our dogs. Being a responsible dog owner involves some simple tasks.
Microchipping and registering is a simple procedure that allows for easy recovery of lost or stolen dogs. Microchipping makes a clear link between a dog and its owner. Having a microchip means they can be reunited quickly with their owners, reducing the stress for dog and owner alike.
Your pets vet will #microchip your dog, along with a growing number of Local Authorities and animal welfare groups. It is the law since 2016.
Like property marking it helps the Gardaí get your property back.