Previous research assessing the effectiveness of structured abstracts has been limited in two respects. First, when comparing structured abstracts with traditional ones, investigators usually have rewritten the original abstracts, and thus confounded changes in the layout with changes in both the wording and the content of the text. Second, investigators have not always included the title of the article together with the abstract when asking participants to judge the quality of the abstracts, yet titles alert readers to the meaning of the materials that follow. The aim of this research was to redress these limitations. Three studies were carried out. Four versions of each of four abstracts were prepared. These versions consisted of structured/traditional abstracts matched in content, with and without titles. In Study 1, 64 undergraduates each rated one of these abstracts on six separate rating scales. In Study 2, 225 academics and research workers rated the abstracts electronically, and in Study 3, 252 information scientists did likewise. In Studies 1 and 3, the respondents rated the structured abstracts significantly more favorably than they did the traditional ones, but the presence or absence of titles had no effect on their judgments. In Study 2, no main effects were observed for structure or for titles. The layout of the text, together with the subheadings, contributed to the higher ratings of effectiveness for structured abstracts, but the presence or absence of titles had no clear effects in these experimental studies. It is likely that this spatial organization, together with the greater amount of information normally provided in structured abstracts, explains why structured abstracts are generally judged to be superior to traditional ones.