This series of maps explores four changes that characterized Boston from 1960 to 2000: White population, college graduates, population age 25-44, and total population. All of Suffolk County was included in the analysis, but “Boston” will be used throughout to describe the study region. Data was collected at the census tract level, and interpolated using cascading density weighting to account for boundary changes that occurred since 1960. All maps display 2000 tract boundaries. Cascading density weighting uses known population distributions from one decade to estimate the distribution in the previous decade among units with different boundaries. This is a preferred alternative to other methods such as areal weighting because it utilizes so much more of the information known about a place in the present to estimate historical data about that place. However, it necessarily introduces a margin of error because there is no way of knowing for sure if populations in historical tract boundaries correspond to present boundaries the way we assume them to through interpolation. The primary visualization methods employed include mapping cluster analysis results and animation of choropleth maps.