cosmo99

If the upper cabinets are built correctly, no other blocking should be necessary with a normal wall and 16" on center studs. There have been some rare cases where a very narrow cabinet might fall between studs, but 99% of the time, I have never run into any problems. Semar (see his comment above), has some good ideas for hanging cabinets, especially ones that don't have a proper nailing surface to start with.