Many U.S. states require redistricting authorities to follow traditional districting principles (TDPs) like the creation of compact districts and respecting the integrity of county and town boundaries. Reformers, academics, and other redistricting experts have long suggested that following such districting principles may enhance representation. Yet, very few academic studies have empirically examined these expectations. Using two measures of geographical compactness and a new measure of respect for political subdivisions (referred to as coterminosity) created with a geographic information system (GIS), the connection between district boundaries and representation is tested. The results show strong evidence that the use of geographic districting principles can enhance dyadic representation, as more compact and more coterminous districts are associated with more positive evaluations of legislative responsiveness and greater citizen-representative communication. Violating TDPs to advance other goals in redistricting like strict population equality between districts thus comes with a clear representational cost.