It was hypothesized that attraction toward another individual is a positive linear function of the proportion of his personality characteristics which are similar to those of S. In the 1st experiment, 151 Ss examined the responses of a stranger to the Repression-Sensitization (R-S) Scale. The stranger responded as S did on .20, .50, or .80 of the items. Analysis of variance indicated that attraction was affected by proportion of similar responses (p<.001) and by repression-sensitization (p<.01). In a 2nd experiment, employing 149 Ss, attitude similarity influenced attraction (p<.001), but repression-sensitization did not. In the 1st experiment, subject-stranger discrepancy in R-S Scale scores was found to influence attraction (p<.001); represser-sensitizer differences were thus artifactual. The relationship between personality similarity and attraction is entirely consistent with the findings of attitude-similarity studies. (PsycINFO Database Record (c) 2016 APA, all rights reserved)