This report describes how undergraduates finance their postsecondary education by presenting data from the 1990 National Postsecondary Student Aid Study. The report discusses the characteristics of undergraduate students and where they attend school, as well as the costs of attendance, and the characteristics of the students who receive federal financial aid. The report describes the characteristics of state and institutional aid recipients as well as the average amount of aid they received from these sources, and provides a broader view of how undergraduates finance their postsecondary education by using a variety of financial resources to help meet attendance costs. Survey results indicated that: (1) about 43 percent of undergraduates received some type of financial aid; (2) the average annual cost of attendance for undergraduates attending public institutions was $8,109, $13,689 for private not-for-profit institutions, and $11,308 for private for-profit institutions; (3) the average tuition and fees for undergraduates attending public institutions was $1,322, $7,051 for private not-for-profit institutions, and $4,792 for private for-profit institutions; (4) about 29 percent of undergraduates received federal financial aid in 1989-90; (5) about 13 percent of undergraduates received state financial aid; (6) about 15 percent of undergraduates received some institutional financial aid; and (7) 16 percent of eligible dependent, and 46 percent of eligible independent students did not receive financial assistance from their parents. Appendices include a glossary and technical notes. (GLR)