The economy of Scotland in the Middle Ages covers all forms of economic activity in the modern boundaries of Scotland, between the End of Roman rule in Britain in the early fifth century, until the advent of the Renaissance in the early sixteenth century, including agriculture, crafts and trade. Having between a fifth or sixth (15-20 %) of the arable or good pastoral land and roughly the same amount of coastline as England and Wales, marginal pastoral agriculture and fishing were two of the most important aspects of the Medieval Scottish economy. With poor communications, in the early Middle Ages most settlements needed to achieve a degree of self-sufficiency in agriculture. Most farms were operated by a family unit and used an infield and outfield system.