Qualitative and quantitative responses to a frustration situation in a sample of 1-year-old normal infants are described. The findings indicated considerable variation in the quality of affect and the span ofinterest. In 1 group of infants, negative affect developed in a relatively short period of time and resulted in disruption ofinterest; in another group of infants, no negative affect developed but instead, a shift in their focus ofinterestoccurred. There was a significant difference in the latency of these two responses. In addition, a small but significant sex effect was observed--females tending to have relatively shorter spans ofinterest. There was no significant effect on these responses due to variations in age, developmental maturity or maternal parity.