High rates of egocentric network turnover are frequently observed but not well explained. About 1,000 respondents to the UCNets survey named an average of 10 names in each of two waves a year apart. Consistent with prior studies, respondents in wave 2 failed to relist about half of the names they provided in wave 1. Asked why, respondents explained that they had forgotten the alter for about 40 percent of the missing names. Other common answers, such as no "occasion... to be in touch," also suggest that the true rate of alters being dropped is probably under 20 percent. Multilevel logit models identified the predictors of alters being dropped (neither relisted nor forgotten) versus retained. Immediate kin were likeliest to be retained and roommates, coworkers, and acquaintances to be dropped. Alters who provided companionship, confiding, advice, and emergency help were especially likely to be retained, as were those to whom respondents felt close. Little about the respondents themselves affected drop rates: having moved recently, having a close friend die, or having had an important relationship break up. Results are consistent with the argument that a tie's degree of constraint (notably being close family) and its balance of rewards determine the likelihood of it being dropped or demoted. Who is Dropped and Why? Methodological and Substantive Accounts for Network Loss Panel studies of egocentric networks commonly report a paradox: Respondents report much turnover among their alters-typically, about half of those named are not renamed-and yet respondents' repopulated networks display notable constancy in traits such as size, composition, supportiveness, and structure (see review below). Our purpose here is to expand our understanding of this phenomena by focusing on the first part of this process: whom respondents drop. We use two waves of UCNets, a survey that administered many name-eliciting questions to about 1,000 adult respondents. Methodologically, we found that (a) many apparently dropped alters were not really dropped, but were simply forgotten; (b) many alters whom respondents failed to re-list nonetheless remained "dormant" and available to the respondents; and (c) respondents positively dropped or demoted alters for several distinct reasons. Substantively, we found that (a) alters who were really dropped-neither re-listed nor simply forgotten-tended to be: extended kin, coworkers, or acquaintances; alters who had not been named as providing key support; and alters who were considered "difficult" (unless they were immediate kin). (b) Respondents who dropped many of their alters were particularly likely to have moved outside the region between waves. These findings suggest, methodologically, that the "true" rate of dropped alters in an adult population is nearer to 20 percent than the conventional 50 percent (depending on how the analyst classifies dropped alters who seemed to have been moved toward the periphery of ego's network). Theoretically, the findings suggest that the likelihood of being dropped ...