there are hundreds of cartórios in rio de janeiro, spread across the whole city, with 12 subdivided cartório districts, all performing various functions and services - one of the main functions of the cartórios, is to provide authentication of signatures, and of official documents, or deeds of any kind - this service is known as the serviços de notas, and is done by the notaries that work in the offices.

one of the very first things anyone who is planning on doing anything in rio de janeiro that would requires documentation and notarizations, is going ahead of everything to notarize and authenticate his or her own signature at a convenient notary office, a procedure called reconhecimento de firma - most legal documents require an authenticated signature, and a cartório near the place of residence would be ideal for this purpose.

another particularly prominent service, provided by the cartórios is just about anything to do with the registering, purchasing, or selling of property and real estate.