Higher education offers people from all walks of life the opportunity to achieve a more secure future for themselves and their families. The country was built in part on the idea that, with hard work and a good education, any American should be able to climb the ladder of social and economic mobility. The very notion of the American Dream is based on that concept of freedom--that people are not condemned to a particular social or economic class. Unfortunately, high college costs are stymieing progress for Americans of limited financial means, undermining basic ideals of opportunity and fairness. Data show wide variation in affordability between students with different income backgrounds. In fact, although the student from the highest income quintile in these analyses could afford to attend 90 percent of colleges in the sample, the low- and moderate-income students with fewer financial resources could only afford 1 to 5 percent of colleges. While it is clear that very few colleges meet a reasonable threshold of affordability for students of modest means, federal, state, and institutional policymakers can help level the playing field. This is the technical appendix for the report. Contents of the appendix include: (1) Research Concept; (2) Student Profiles; (3) Net Price Calculators; (4) Sample Colleges; (5) Additional Affordability Models; and (6) Glossary of Key Terms. [To view the report, "Limited Means, Limited Options: College Remains Unaffordable for Many Americans," see ED591563.]