In this dissertation, we develop a model to investigate some implications of single and multiple submissions policies of academic journals. We make the following four assumptions. First, authors are identical and they produce papers with the same quality distribution; Second, there are only two journals and their quality standards are common knowledge; Third, the errors in the referee's assessment of papers' quality are uncorrelated. Finally, if a paper is rejected by a journal it can not be resubmitted to the same journal in the future. We find that if multiple submissions were allowed, the average quality of accepted papers could be higher or lower than those in the single submission case. Therefore, a multiple-submission policy may not necessarily deteriorate the quality of published papers. In addition, we find that, as authors become less patient they are more likely to choose multiple submissions, and if authors are sufficiently patient they never choose multiple submissions. Thus, authors who are not very patient suffer more from the prevailing policy of prohibiting multiple submissions. We also found that under the situation that authors are patient enough, whether multiple-submission may occur in their optimal submission strategy depends on the magnitude of publication benefit in the high quality journal. When the publication benefit in the high quality journal is small enough, authors will never include multiple-submission in their optimal strategy.