The National Household Education Survey (NHES) is a telephone survey of the noninstitutionalized civilian population of the United States that collects data on educational issues that are best explored through contact with households rather than with institutions. The NHES has been conducted in 1991, 1993, 1995, and 1996. In the 1996 NHES (NHES:96), the topical components were parent/family involvement in education and civic involvement. The 1996 expanded screener feature included a set of questions on public library use. This working paper presents information on the potential for undercoverage bias in estimates from the NHES:96. Estimates from the NHES:96 are subject to bias because only households with telephones were sampled. Data from the October 1994 and November 1994 Current Population Survey of the Bureau of the Census are used to estimate the potential size of the undercoverage bias of the estimates. The analysis shows that the coverage biases for estimates of household characteristics are not very large. For estimates of voter participation of adults, the coverage biases are somewhat larger. This is due mainly to extreme differences in voter participation characteristics between adults in telephone and nontelephone households. For the adult civic involvement questions in the NHES:96, the differences may not be so large. However, undercoverage bias for some subgroups in the NHES:96 may be problematic, since coverage biases for Black households and persons, and, to a lesser extent, Hispanic households and persons, were larger than for the population as a whole. Overall, findings about the NHES:96 support the use of telephone data collection as a cost-effective survey procedure. An appendix contains nine tables from the analyses. (Contains 11 references.) (SLD)