These two buildings across the street from each other in San Francisco were constructed nearly a century apart, but they both have the same form. Seven story mixed-use built to the sidewalk. The new building may look very different, architecturally speaking, from the old one, but it is identical in form. Often when people argue about compatibility of design in new construction they obsess about architectural style and ignore the form of the buildings. This is something many community "design review boards" miss; especially when it comes to single family homes. It doesn't have to look like a replica of existing buildings to be compatible with the character of the neighborhood.