The same linguistic data can often be analyzed in multiple ways, using different theoretical assumptions. Systematic comparison of the competing analyses requires understanding how the theories give rise to them, and the consequences and predictions implied by each set of assumptions. In this paper, we compare two theories of segmental harmony: Agreement-by-Correspondence (ABC) (Rose & Walker 2004; Hansson 2010; Bennett 2015), and Agreement-by-Projection (ABP) (Hansson 2014). We analyze typologies in each through Property Theory (Alber, DelBusso & Prince 2016; Alber & Prince 2016, in prep.). Typological analysis shows the strong parallelism between the different proposals at both the extensional and intensional levels. Not only do both theories predict the same set of surface distinct languages, but these follow from a similar internal structure. We show how the ABP proposal formally combines two ABC constraints, collapsing the ABC typology along the correspondence/noncorrespondence dimension.