Steve,

The next two parent categories that I use the most for our Engineers,
after the project that is, are the following two:

CORRESPONDENCE AND MEMORANDA: ADMINISTRATIVE
This record series consists of routine correspondence and memoranda of a
general nature that are associated with administrative practices but
that do not create policy or procedure, document the business of a
particular program, or act as a receipt.  
RETENTION:
a) Record copy.  3 fiscal years

CORRESPONDENCE AND MEMORANDA: PROGRAM AND POLICY DEVELOPME
This record series consists of correspondence and memoranda documenting
policy development, decision-making, or substantive programmatic issues,
procedures, or activities.  
RETENTION:
a) Record copy.  5 fiscal years provided applicable audits have been
released.  

I copied these directly from our state approved Retention Schedule.
A Program could be like "Infrastructure Improvements", "Customer
Support" or "Commercial Aircraft Engineering"
Meanwhile most E-mails (or not) will relate to a specific project others
will relate just to a Program in a broad kind of way. 

So I recommend for you to create categories depending on the Mayor
Programs your Engineers are working on and then to work with Management
to create retentions for the categories that are based on the
Administrative, Historical and Legal Value of the correspondence they
relate to.
The Retention shown above are just the legal minimum in the State of
Florida.

I bet it has to be a huge undertaken to bring order out of chaos when
you work for international company as yours. 

Good Luck and hope this was food for thought!

Simon T. De Witt 
Records Information Analyst 
Tampa Bay Water 
2575 Enterprise Road 
Clearwater, FL 33763-1102 
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