Although historians have referred occasionally to the large sizes of families in eighteenth-century America, few attempts have yet been made to establish reliable or even suggestive data about family and household size in the British colonies or the new United States. Local records could provide data for individual families, of course, and the abundant genealogical evidence which has been collected for American families could be used in determining the sizes of families in many different periods and places. More general data, however, covering larger numbers of families, more places, and different periods of time are more difficult to gather in most of the colonies and states prior to 1790. The most useful sources for such data are censuses, particularly those which include data on the number of families, houses, and total population in given places. Unfortunately, though, such censuses appear to be exceedingly rare, judging by the printed versions which are presently available. In fact, only thirteen separate censuses for colonies or for states appear to exist for the eighteenth century which contain information about families or housefuls: one taken in 1764 of towns in fourteen counties in the Province of Massachusetts (including three counties now in the present state of Maine); one taken in 1774 of twenty-nine towns in the Province of Rhode Island; and the extraordinarily detailed listings of heads of families in towns, counties, and districts of eleven states taken in 1790. Together, they constitute invaluable sources for the history of the family in eighteenth-century America.