From NDMSO: 

>>> Rebecca S Guenther 1/27/2009 >>>
When USMARC harmonized with CANMARC, the format was named MARC 21. 

Further information is here:
http://www.loc.gov/marc/annmarc21.html 

Since that time, many other national libraries have moved from their national formats to MARC 21, including (among others), the UK, Germany, Finland, and Spain.

Rebecca S. Guenther                                                       
 Senior Networking and Standards Specialist                  
 Network Development and MARC Standards Office     
 Library of Congress   
 101 Independence Ave. SE                                       
 Washington, DC 20540                                                      
 Washington, DC 20540-4402                                          
 (202) 707-5092 (voice)    (202) 707-0115 (FAX)           
 [log in to unmask] 

---------- Forwarded message ----------
Date: Fri, 23 Jan 2009 09:39:54 -0000
From: "Brown, Alan" <[log in to unmask]>
Reply-To: Code for Libraries <[log in to unmask]>
To: [log in to unmask] 
Subject: Re: [CODE4LIB] marc21 and usmarc

At 22 January 2009 16:28 Eric Lease Morgan wrote:

> Does anybody here know the difference between MARC21 and USMARC?
> 
> I am munging sets of MARC bibliographic data from a III catalog with
> holdings data from the same. I am using MARC::Batch to read my bib'
> data (with both strict and warnings turned off), insert 853 and 863
> fields, and writing the data using the as_usmarc method. Therefore, I
> think I am creating USMARC files. I can then use marcdump to... dump
> the records. It returns 0 errors.     

Eric, This isn't an encoding thing is it? I know that a number of III
catalogues still encode their diacritics using the MARC8 version of
USMARC. We have changed ours to Unicode now, but we did have an issue of
the catalogue outputting unicode records that weren't tagged as such in
the leader and so couldn't be identified as proper MARC21 (current
version of USMARC). III have solved this with their latest release. This
issue had me scratching my head with a lot of my MARC::Record scripts,
but generally they failed quite spectacularly.

regards

Alan Brown
-- 
Alan Brown
Library Systems Liaison Officer
Resource Services
Bury Libraries
Textile Hall
Manchester Rd
Bury
BL9 0DG
Tel 0161 253 5877
Fax 0161 253 6003
http://www.bury.gov.uk/libraries 
http://library.bury.gov.uk 
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