Many government agencies use MoUs to define a relationship between departments and agencies. For example, the NSA may have a MOU between it and the USAF for certain satellite data, ie; who owns the data.
Under the FOIA, you can ask for MOUs for different agencies. Below, you will find those MOUs which have currently been obtained.
National Reconnaissance Office (NRO)
National Oceanic and Atmospheric Administration (NOAA)