The 3-year psychological effects of presymptomatic DNA diagnosis for Huntington's disease are described in 20 identified carriers of the Huntington's disease gene (mean age = 31 years), 29 noncarriers (mean age = 32 years), and 37 partners. The Intrusion and Avoidance subscales of the Impact of Event Scale (M. J. Horowitz, N. Wilner, & W. Alvarez, 1979) and the Beck Hopelessness Scale (A. T. Beck, 1986; A. T. Beck, A. Weissman, D. Lester, & L. Trexler, 1974) measured psychological distress at 4 time points: baseline (before disclosure of test results) and 1 week, 6 months, and 3 years after testing. Multivariate testing on course of distress revealed similar patterns of intrusive thoughts about Huntington's disease over the 3-year follow-up in carriers and noncarriers but showed opposite patterns of avoidance at the 6-month assessment. One week after disclosure, carriers had increased and noncarriers had decreased levels of hopelessness. These effects disappeared after 6 months and did not recur. Carrier partners followed the same course of distress as carriers. Carrier partners with children were significantly more distressed than those without offspring. Noncarrier partners were significantly less distressed than noncarriers after 3 years.