In Poland it is required by law for a given name to clearly indicate the person’s gender. Registering names, which do not appear on an official list of names is also problematic or even impossible.
As in other European countries children usually take the surnames of their fathers. It is though becoming popular to take two surnames (one from each parent). For example, Walczak-Bukiewicz, Walczak from the father and Bukiewicz from the mother. Female spouses often have hyphenated surnames, the first part her maiden name, the second the surname of her husband. It is extremely rare for women not to take their husband’s surname. Similarly, children generally do not take the mother’s surname, except as in a double-barrelled surname.
Most confusingly for non-Polish speakers is, perhaps, that females who take their husband’s surname may take a feminized form of the name. The wife of Mr Kowalski may be Mrs Kowalska. Polish surnames also take different endings according to a complex set of declensions. Mr Kowalski and Mrs Kowalski together become Mr and Mrs Kowalscy.