Advisor: Elizabeth Thompson A major topic in statistical genetics is discovering the locations of genes contributing to complex traits through linkage analysis. The likelihood of a genetic marker controlling the expression of the trait is calculated using estimated identity-by-descent (IBD) graphs, which indicate whether copies of the marker shared among individuals are inherited from a common ancestor. Methods for estimating IBD graphs either use pedigree or population relationships between the individuals, and do not scale to a large number of individuals. We present a stepwise, scalable approach to linkage analysis that combines estimates of IBD graphs obtained at population and pedigree levels. The combination of population and pedigree information gives additional power for trait detection, and increases the number of individuals that can be used in the analysis.