This study examined how poverty and residential mobility influence low-income adults' persistence in family literacy programs in Pennsylvania. Twelve out of 20 program directors reported that learners typically moved at least once a year. In five of these high-mobility programs moving was reported to significantly hinder persistence. Geographic location and the availability of inexpensive and subsidized housing increased mobility. The 17 learners the authors interviewed moved 78 times in the previous five years, for an average of once per year. One-half of the moves were within 15 miles, yet even short distance moves often delayed progress and disrupted program participation. Although residential mobility did not hinder persistence in all programs, it is part of a constellation of poverty-related problems (e.g., poor health, lack of child care and transportation) that pose challenges for learners to attend classes regularly and meet their educational goals. (Contains 2 tables and 2 endnotes.)