SDA is a data delivery and analysis system. SDA@CHASS provides access to: Canadian Public Use Microdata Files (PUMFs), mainly survey data available from the Statistics Canada Data Liberation Initiative (DLI); Canadian aggregate census data files; plus a few other collections of data. Users can analyze datasets online, download data, or consult relevant documentation.This collection of on-line databases and custom built search and retrieval programs are maintained by Computing in the Humanities and Social Sciences (CHASS) at the University of Toronto.