The growth of the mutual fund industry and the accompanying competition among intermediaries should lead to progressively lower costs to shareholders, based on economic theory. This dissertation is comprised of three studies which examine shareholder costs among mutual funds to test this theory. In each study the expense ratios of mutual funds are examined, while one study also includes an examination of commission structures. In Essay 1, the effect of participation in a supermarket No Transaction Fee program on a fund’s expense ratio is examined. In addition, the change in characteristics of these participants during a difficult market period is studied. Essay 1 finds that NTF participation leads to higher initial expense ratios but that continued participation depends on the program’s ability to pay for itself. In Essay 2, market segmentation within the fund industry is examined for this same time period. Essay 2 finds increased market segmentation over a five year period and finds evidence of competitive pricing only among certain segments. Retail investors who invest in no-load funds appear to benefit from competitive pricing more than those who pay commissions. There is evidence of cost shifting during this time period, as funds lower expense ratios but increase commissions. In Essay 3, expense ratios of common funds within state-sponsored defined contribution plans are examined. Essay 3 finds evidence of market segmentation among the various states. Plan size may have some effect on the setting of expense ratios, but the effect does not appear to be economically significant. Number of participants has no significant effect on the expense ratio. State population displays some significance, such that funds actually charge more for larger states. Wealth of the state, on the other hand, may result in lower expense ratios. Overall, competitive pricing within the mutual fund industry is limited to certain market segments and may be dependent on the channel of distribution.