The Spanish and Mexican colonial censuses are essential for researching New Mexican roots. The 1790 census lists the head of household along with age and occupation. Spouses are named and the ages are given for other household members. The 1823 and the 1845 censuses list names and ages for every person in the household. This newly revised edition improves the original book first published in 1975. The entire book has been re-typed in a more readable font, corrections have been made, and a new index points to page numbers rather than microfilm frames. This revised edition also includes the vital 1790 census for Taos which was not in the original book.