Interruptions and multitasking have received a great deal of attention from researchers. The present study is the first to examine task self-efficacy along with interruptions in an experimental multitasking framework. Perceptions of resumption lag times and task rehearsal were also examined. Participants (N= 110) completed a primary task (puzzle) with some being interrupted to pursue a secondary task (a word search) either once or four times. Uninterrupted participants completed the puzzle 26% faster than those interrupted once and 30% faster than those interrupted four times. However, self-efficacy predicted performance much more strongly than did interruptions, and therefore should receive more attention in future studies. Participants generally disagreed that they experienced resumption lags or task rehearsal. Practically, the results indicate that training to the point of high self-efficacy on tasks will do more to enhance performance than would eliminating interruptions. In reality, such training is likely easier to accomplish.