The hippocampus is made up of a diverse collection of neurons with complex physiological properties. I will describe our efforts to understand the functional diversity of these neurons. Most of our work has focused on principal neurons (pyramidal neurons in CA1 and subiculum), where we have described a role for dendritic excitability in synaptic integration and plasticity, as well as diversity in the structure, function, and plasticity in two distinct types of pyramidal neurons. In addition, I will describe recent work demonstrating the importance of the axon as an integrative structure in some inhibitory interneurons in the hippocampus.