The present research was designed to investigate the summative and interactive effects of the determinants of interpersonal attraction on attraction behaviour. Sixty male and sixty female students within the age group of 18-25 years participated in two experiments separately, wherein they responded to each of 16 experimental conditions on interpersonal judgement scale. The attraction data were analysed using a 2(4 x 2 x 2) factorial design with repeated measure on three independent variables: physical attractiveness (attractive vs unattractive male and female targets), personality similarity-dissimilarity and reciprocity (liking vs disliking). The main effects of these determinants of interpersonal attraction were found highly significant (p < .01) in both experiments. ANOVA also yielded significant inter-action between physical attractiveness and similarity; physical attractiveness and reciprocity. The findings supported the stereotype "What is beautiful is good", and highlighted the fact that the determinants of interpersonal attraction summate as well as interact in producing attraction within the framework of reinforcement model.