Physical attractiveness is the strongest predictor of romantic interest for men and women. Men's attraction is driven far more by partner traits than women's. Women's attraction relies more on their own self characteristics. Partner physical attractiveness overrides personality, values, politics, and attachment styles. Similarity between partners predicts zero attraction. Reciprocity shows mild support in dyadic effects. Women rate athletic men higher (r=0.48). Big Five traits fail to predict any interest. Speed-dating reveals spontaneous beauty bias over rational long-term preferences. Both sexes equally prioritize beauty despite evolutionary sex difference claims. Beauty effect persists even in events seeking long-term partners. Study used 108 college students in real speed-dating. Photos rated highly reliably (ICC=0.86). Initial 5-minute dates expose raw attraction drivers. Personality irrelevant in thin-slice encounters. Authors note conscious ideals differ from actual feelings.