First name or title
It is usual for people to have very long names. Usually the first in the list is the first name, the rest (as many as five or six, although not usually all set out on business cards etc) are family names. The exception is that some women’s names are compound, usually with Maria as the first part (e.g. Maria Luisa, Maria Teresa), in which case it is common to drop the “Maria” and just use the second half (Luisa, Teresa, etc).
The rest of the family names are built up from various generations alternating through the Mother’s and Father’s sides. The very last name is usually the last names for purpose of addressing a person but it is common for the last two to be used – it’s a matter of listening how they are referred to by others but you won’t offend by just using the last name as family name. Note that this is slightly different from the similar Spanish system of names.
Titles in Portugal are a minefield which can take years to traverse.
The simplest is not to try to understand and to use the English Mr lastname and Ms lastname. Do not use first names unless invited.
Don’t be alarmed if they call you Mr/Ms/Mrs firstname (e.g. “Mr John”) or slip in a Dr or whatever, even if you’re not an MD or PhD. They may well use Mrs, without any intended indication of marital status, as there is none in the Portuguese and many have not been taught at school that the “Ms” title was invented 50 years ago and has been in regular use for at least 30.
In many companies close and long term colleagues can still refer to each other quite formally.
If you really want to use Portuguese titles, you have to be careful to avoid giving offence. Otherwise, all you need to know is that the Dr title refers to someone with a normal degree (slightly more than Bachelor’s ) and not a PhD or MD. I explain the details in the next section for the curious.
People will not be offended if you have difficulty pronouncing their name but will be very pleased if you ask them to explain how to pronounce it correctly.
The system of Portuguese titles
Having a Degree entitles you to use “Dr” (or Dra = “Doutora” for a woman), unless it’s in engineering in which case the title is Eng or Enga (“Engenheiro”, “Engenheira”) or in architecture in which case it’s Arq or Arqa (“Arquitecto”, “Arquitecta”)
Having a Masters Degree theoretically entitles you to the title “Mestre” but this is only used in formal or written situations in the academic world.
People with doctorates (PhD but not MD) are titled as Professor (”Professor Doutor”), so don’t assume a Professor holds a professorial chair or is even a university teacher.
When addressing someone by last name use “Senhor (or Doutor etc if applicable) lastname” for a man and “Senhora Dona firstname” for a woman without a degree etc or “Doutora (etc) lastname” “Senhor firstname” is used but is often for “inferior” ranks or foreigners whose surnames they can’t manage. The Brazilian usage of plain “Dona firstname” is usually incorrect in Portugal but is slipping into less careful usage through the Brazilian soaps on TV.
Just to add further confusion Senhor (etc) firstname lastname is also not uncommon, as is addressing people very informally (even close friends) just by lastname.
Unfortunately, being titled “Dr” etc is a business and social advantage and will get you meetings and respect you might not otherwise get. Like it or not, if you’re going to work here for a while and have a degree, get them to use the title. The trouble is, you should never introduce yourself as “Dr.Smith” (or whatever), unless you’re a PhD/MD and speaking in English to someone who understands the US/UK system, as this is very bad form. Instead, slip in a casual reference to your university or degree somewhere in a conversation and it will probably be picked up, although foreign names seem to confuse the system sometimes and you’ll still be a Senhor or Senhora Dona. The last resort is to get an assistant or secretary to refer to you in Portuguese as “Dr Smith” to a third party. Yes, it is a huge pain.
I won’t explain the further various degrees of formality/informality in address here, as that requires more Portuguese, several pages of explanation and a Byzantine mindset.