Changes in Latino neighborhoods in Tucson, Arizona that occurred between 1990 and 2010 were studied. The overall Latino population increased substantially within the larger metropolitan area during the target time period. Neighborhoods were selected that had changed to become predominantly Latino during the target time period based on maps measuring ethnic clusters. Research was designed to characterize Latino neighborhoods in Tucson in terms of transformation. Methodology for comparison between changed and unchanged neighborhoods was developed. Observations were made in the three new neighborhoods, as well as in three historically Latino neighborhoods that experienced little change during the same time period. Interviews were conducted with residents from each neighborhood. Exploratory findings were made regarding the transformation of the neighborhoods with increased Latino populations. Findings showed that two areas of transformation increased largely because of the rise of higher density rental housing while one area transformed because two new affordable subdivisions were created within the studied time period. One new neighborhood's physical domain changed from an undeveloped land to a neighborhood with tract style houses. The historical areas have transformed in different ways including a decrease in crime and an increase in the younger population. The historical areas have experienced little change in the physical domain. All neighborhoods studied had evidences of a Spanish speaking population, and have businesses that cater to the surrounding Hispanic population.