One of the most peculiar aspects of the Roma's settlements is their immersion and dispersion in the midst of the Gadje (non-Gypsies). In order to maintain dispersion, based on economic and sociopolitical considerations, they are both nomadic and sedentary. Most of the Roma live in caravans and camp in locales that are either less than ideal or specially prepared by the local authorities, on the outskirts of town. However, a number of families live in permanent dwellings, ranging from simple huts to luxurious villas. A fair degree of mobility is, nevertheless, found even among those living in fixed abodes; removals are frequent and they often alternate between house and caravan. Dispersion is achieved by maintaining a minimal density of Roma in any given locality. A local group rarely consists of more than fifteen nuclear families.