In well-mixed populations, correlational selection that associates different traits within individuals simply favours associations that increase the fitness of their carriers. Natural populations, however, tend to be genetically-structured due to limited dispersal. In my talk, I will present some general theory on the consequences of such structure for correlational selection and for patterns of variation in complex, multi-trait phenotypes. Using an example on the coevolution between dispersal and sociality, I will then illustrate how our results can help understand intra-specific variation and the genetic basis of complex social phenotypes.