AYUNTAMIENTO. The ayuntamiento was the principal governing body of Spanish municipalities. It functioned as the town council and had a wide range of administrative duties. Its size varied and was generally based on the population of the town. The council members consisted of the alcalde, who served as president, a varying number of regidors (see REGIDOR) or councilmen, and a síndico procurador, the equivalent of a city attorney. Other local administrators-police chiefs and fine collectors, for instance-sometimes held positions in the council, though often these additional members were not allowed to vote. The ayuntamiento was in most cases not a democratic institution. Often it received little voluntary support from the people it represented. Many offices were inherited, and others were sold by the crown or their current holders. Although elected officials did exist, by the late colonial period many ayuntamientos had to resort to forced service, for often few men of consequence volunteered to serve. Spanish colonists in America commonly referred to the ayuntamiento as the cabildo, though this term first meant the building in which the council met.
Full article on the Texas State Historical Association's Handbook of Texas Online