According to the Garland Encyclopedia article written by the expert of the Portugal traditional music and polyphony, Castelo-Branco (2000), vocal polyphonic singing occurs in few isolated pockets of northern and southern Portugal. In the mountainous north part of Portugal these are the districts of Viana do Castelo, Braga and Aveiro. In the central part of the north of Portugal there is the district of Viseu, and in central-east Portugal the district of Castelo-Branco. Another important region of traditional polyphony is in the district of Beja in the southern part of Portugal.
The polyphonic traditions are mostly connected to the European major-minor harmonic system. Two-, three- and four-part singing in Portugal is based on European triadic harmonies and parallel thirds.
The scales are mostly European major and minor, but in the Beja and Castelo-Branco districts older scale systems are also used. The melodies in the central, eastern and south Portugal polyphonic traditions use melismatic ornaments (but not in the Northwestern districts). In most of the polyphonic regions women sing polyphonic songs. Only in southern Portugal (district Beja in Alentejo) is polyphony primarily a part of the male repertoire.