GED testing candidates have many options available to them to prepare for the GED Test, including adult education classes, practice tests, and self-study. This study focused on candidates who voluntarily took the GED Test and could choose freely among preparation activities. We examined GED Test preparation activities and created eight mutually exclusive test preparation profile groups: public school adult education with or without a practice test, community college adult education with or without a practice test, individual study with or without a practice test, practice test only, and "none". The final sample included 90,032 U.S. candidates who completed the GED Test in 2004 and fell into one of the eight test preparation profile groups. Candidates in the study most often reported studying on their own without a practice test (29 percent) or studying in a public school adult education program without a practice test (28 percent). A smaller proportion studied in a community college adult education program without a practice test (13 percent) or did not prepare at all (14 percent). The public school and community college adult education profile groups had mean GED scores 25 to 34 points higher for candidates who took a practice test. The individual study group means were 20 points higher for candidates who took a practice test. Among the profile groups, the group members who studied individually with a practice test and the "none" group scored the highest on average. The lowest mean scores were observed in the group who indicated public school adult education preparation without a practice test. All groups' content areas and battery mean scores were higher than the passing requirement (410 and 2,250, respectively). The group with the highest pass rates was the individual study with a practice test group, and the lowest pass rates were recorded for the public school adult education without a practice test group. A technical appendix is included. (Contains 11 tables.)