MODS to MARC 21 Mapping
Version 3.0

December 2003

This mapping is for use with MODS Schema version 3.0. The mapping for use with the MODS Schema version 2.0 is located online at: www.loc.gov/standards/mods//mods2marc-mapping.html.

Introduction
Contents of Elements
Mapping
Leader and Fixed Fields
Changes Made for MODS Version 3.0

1. Introduction

This mapping provides equivalencies between data elements in MODS and those in MARC 21. Initially, a MODS record is converted to MARCXML. Further conversion work is required to create a MARC 21 (ISO 2709) record. Since MARC 21 includes many more data elements than MODS, this mapping suggests a single MARC 21 equivalent for each MODS element, although there may be other equivalents. The MARC 21 to MODS mapping provides multiple MARC 21 data elements appropriate for a given MODS element.

This document is intended for use in first converting a MODS record to MARCXML and then to a MARC 21 (ISO 2709) record. Since MODS data is not as granular as MARC 21 data and some MARC 21 subfields are concatenated into one MODS field, some data may map to inappropriate MARC 21 fields or subfields. Consequently, some conversions will result in some loss of data identification.

Items highlighted in red indicate changes made to MODS in Version 3.0.

2. Contents of Elements

titleInfo	note
name	subject
typeOfResource	classification
genre	relatedItem
originInfo	identifier
language	location
physicalDescription	accessCondition
abstract	extension
tableOfContents	recordInfo
targetAudience

3. Mapping

title <titleInfo>
<title> with no <titleInfo> type attribute and		245 $a with ind1=1
	<subTitle>	245 $b
	<partNumber>	245 $n
	<partName>	245 $p
	<nonSort></nonSort>	ind2=number of characters in content;
		ind2=0 if <nonSort> not present

<title> with <titleInfo> type="abbreviated" and		210 $a with ind1=1 ind2=blank
	<subTitle>	210 $b

<title> with <titleInfo> type="translated" and		246 $a with ind2=1
	<subTitle>	246 $b
	<partNumber>	246 $n
	<partName>	246 $p

<title> with <titleInfo> type="alternative" and		246 $a ind1=3 ind2=blank
	<subTitle>	246 $b
	<partNumber>	246 $n
	<partName>	246 $p
	displayLabel="content"	246 $i

<title> with <titleInfo> type="uniform" and		240 $a with ind1=1
	with <name><role><roleTerm> with type="code"
	cre or
	<name><role><roleTerm> with type="text"
	creator and
	<partNumber>	240 $n
	<partName>	240 $p
	<nonSort></nonSort>	240 ind2=number of characters in data;
		240 ind2=0 if <nonSort> not present

<title> with <titleInfo> type="uniform" and		130 $a with ind2=blank
	<partNumber>	130$n
	<partName>	130 $p
	<nonSort></nonSort>	130 ind1=number of characters in data;
		130 ind1=0 if <nonSort> not present

name <name>
<name> with no type attribute		720 ind1=blank ind2=blank
	<namePart>	720 $a
<name> with type="personal" and		100 ind1=1 ind2=blank
	<role><roleTerm> with type="text"
	creator or
	<role><roleTerm> with type="code"
	cre
<name> with type="personal" and no		700 ind1=1 ind2=blank
	<role><roleTerm> with type="text" or
	<role><roleTerm> with type="text" is not "creator" or
	<role><roleTerm> with type="code" is not "cre"
	<namePart>	100, 700 $a
	<namePart> with type="date"	100, 700 $d
	<namePart> with type="termsOfAddress"	100, 700 $c [for titles associated with a name]
	<role><roleTerm> with type="text"	100, 700 $e
	creator
	<affiliation>	100, 700 $u
	<role><roleTerm> with type="code"	100, 700 $4
	content
	<displayForm>	887 $a ind1=blank ind2=blank
	<description>	100, 700 $g

<name> with type="corporate" and		110 ind1=2 ind2=blank
	<role><roleTerm> with type="text"
	creator or
	<role><roleTerm> with type="code"
	cre
<name> with type="corporate" and no		710 ind1=2 ind2=blank
	<role><roleTerm> with type="text" or
	<role><roleTerm> with type="text" is not "creator" or
	<role><roleTerm> with type="code" is not "cre"
	<namePart> (1st usage)	110, 710 $a
	<namePart> (each additional)	110, 710 $b
	<role><roleTerm> with type="text"	110, 710 $e
	content
	<role><roleTerm> with type="text"	110, 710 $4
	content
	<displayForm>	887 $a ind1=blank ind2=blank
	<description>	110, 710 $g

<name> with type="conference" and		111 ind1=2 ind2=blank
	<role><roleTerm> with type="text"
	creator or
	<role><roleTerm> with type="code"	711 ind1=2 ind2=blank
	cre
<name> with type="conference" and no
	<role><roleTerm> with type="text" or
	<role><roleTerm> with type="text" is not "creator" or
	<role><roleTerm> with type="code" is not "cre"

	<namePart>	111, 711 $a
	<role><roleTerm> with type="text"	111, 711 $4
	content
	<role><roleTerm> with type="code"	111, 711 $4
	content
	<displayForm>	887 $a ind1=blank ind2=blank
	<description>	111, 711 $g

typeOfResource <typeOfResource>	Leader/06
text	a ; also: Establish 008=BK if
	<originInfo><issuance>="monographic"
	Establish 008=SE if
	<originInfo><issuance>="continuing"
text and attribute manuscript="yes"	t ; also: Establish 008=BK
cartographic	e ; also: Establish 008=MP
cartographic and attribute manuscript="yes"	f ; also: Establish 008=MP
notated music	c ; also: Establish 008=MU
notated music and attribute manuscript="yes"	d ; also: Establish 008=MU
sound recording-nonmusical	i; also: Establish 008=MU
sound recording-musical	j ; also: Establish 008=MU
still image	k ; also: Establish 008=VM note that projected still images are more appropriately included in code g (e.g. slides)
moving image	g ; also: Establish 008=VM
three dimensional object	r ; also: Establish 008=VM
software, multimedia	m ; also: Establish 008=CF
mixed material	p ; also: Establish 008=MM
if attribute collection="yes"	Leader/07 "c"

NOTE: Establish 008 based on above Leader/06 codes and specified 008. The first typeOfResource* determines type of MARC 008.*
If there is more than one typeOfResource, subsequent instances are mapped to 006/00 with code as above.

genre <genre>
<genre authority="marcgt">	Various positions; map to 008 type previously established by typeOfResource.
	In cases of 007, establish the 007 and map.
	When there are multiple positions (e.g. 008/24-27) map each succeeding position until exhausted.
abstract or summary		008/24-27 BK, SE (code a)
art original		008/33 VM (code a)
art reproduction		008/33 VM (code c)
atlas		008/25 MP (code e) and
		007/01 MP (code d) with 007/00 (code a)
autobiography		008/34 BK (code a)
		008/30-31 MU (code a)
bibliography		008/24-27 BK, SE (code b)
biography		008/34 BK (code d) 008/30-31 MU (code b)
catalog		008/24-27 BK, SE (code c)
chart		008/33 VM (code n)
comic strip		008/33 BK (code c)
conference publication		008/29 BK, SE (code 1) 008/30-31 MU (code c)
database		008/21 SE (code d) 008/26 CF (code e)
dictionary		008/24-27 BK, SE (code d)
diorama		008/33 VM (code d)
directory		008/24-27 BK, SE (code r)
discography		008/24-27 BK, SE (code k)
drama		008/33 BK (code d) 008/30-31 MU (code d)
encyclopedia		008/24-27 BK, SE (code e)
essay		008/33 BK (code e) 008/30-31 MU (code e)
festschrift		008/30 BK (code 1)
fiction		008/33 BK (code 1) 008/30-31 MU (code f)
filmography		008/24-27 BK, SE (code q)
filmstrip		008/33 VM (code f)
flash card		008/33 VM (code o)
folktale		008/30-31 MU (code o)
font		008/26 CF (code f)
game		008/26 CF (code g)
graphic		008/33 VM (code k)
globe		008/25 MP (code d) and 007/00 (code d)
handbook		008/24-27 BK, SE (code f)
history		008/30-31 MU (code h)
humor, satire		008/33 BK (code h) 008/30-31 MU (code k)
index		008/24-27 BK, SE (code i)
instruction		008/30-31 MU (code i)
interview		008/30-31 MU (code t)
kit		008/33 VM (code b)
language instruction		008/30-31 MU (code j)
law report or digest		008/24-27 BK, SE (code w)
legal article		008/24-27 BK, SE (code g)
legal case and case notes		008/24-27 BK, SE (code v)
legislation		008/24-27 BK, SE (code l)
letter		008/33 BK (code i)
loose-leaf		008/21 SE (code l)
map		007/01 MP (code j) with 007/00 (code a)
memoir		008/30-31 MU (code m)
microscope slide		008/33 VM (code p)
model		008/33 VM (code q) and
		007/01 MP (code q) with 007/00 (code a)
motion picture		008/33 VM (code m)
newspaper		008/21 SE (code n)
novel		008/33 BK (code f)
numeric data		008/26 CF (code a)
patent		008/24-27 BK (code j)
periodical		008/21 SE (code p)
picture		008/33 VM (code i)
poetry		008/33 BK (code p)
		008/30-31 MU (code p)
programmed text		008/24-27 BK, SE (code p)
realia		008/33 VM (code r)
rehearsal		008/30-31 MU (code r)
remote sensing image		007/01 MP (code r) with 007/00 (code a)
reporting		008/30-31 MU (code g)
review		08/24-27 BK, SE (code o)
series		008/21 SE (code m)
short story		008/33 BK (code j)
slide		008/33 VM (code s)
sound		008/26 CF (code h) 008/30-31 MU (code s)
speech		008/33 BK (code s) 008/30-31 MU (code l)
statistics		008/24-27 BK, SE (code s)
survey of literature		008/24-27 BK, SE (code n)
technical drawing		008/33 VM (code l)
technical report		008/24-27 BK, SE (code t)
theses		008/24-27 BK, SE (code m)
toy		008/33 VM (code w)
transparency		008/33 VM (code t)
treaty		008/24-27 BK, SE (code z)
videorecording		008/33 VM (code v)
web site		008/21 SE (code w)

NOTE: Those MARC elements that have multiple positions (008/24-27BK, SE, 008/30-31, MU) allow for multiple genre codes. If more than one instance of <genre> place in succeeding positions until positions exhausted. If more codes than positions, leave out subsequent ones.
NOTE: If 008 is established to a variety other than that in the mapping (based on typeOfResource), retain data and map to: 655 $a ind1=blank ind2=7 $2="marcgt".

<genre> with authority is not "marcgt"		655 $a ind1=blank ind2=7
<genre authority="content">		add $2=content of authority attribute

originInfo <originInfo>
<place><placeTerm> with type="code" and authority="marccountry"		008/15-17; if multiple <place><placeTerm type="code"> repeat first and put subsequent in 044 $a, repeating $a
<place><placeTerm> with type="code" and authority="iso3166"		044 $c ind1=blank ind2=blank

<place><placeTerm> with type="text"		260 $a ind1=blank ind2=blank
<publisher>		260 $b
<dateIssued> or with point="start" or no point attribute		260 $c
<dateIssued> with point="end"		260 $c [Generate a hyphen before date]
<dateIssued> with encoding="marc"		008/07-10 (008/06="s")
<dateIssued> with point="start" or no point attribute and		008/07-10 (008/06="m")
	encoding="marc"
<dateIssued> with point="end" and		008/11-14 (008/06="m")
	encoding="marc"
<dateIssued> with qualifier="questionable"		260 $c [Generate a question mark after the date]
<dateCreated>		260 $g
<dateCaptured> with encoding="iso8601"		033 ind1=0 ind2=0 $a
<dateCaptured> with point="start" or no point attribute and		033 ind1=2 ind2=0 first $a
	encoding="iso8601"
<dateCaptured> with point="end" and		033 ind1=2 ind2=0 second $a
	encoding="iso8601"
<dateOther>		046$c
<dateOther> with point="start" or no point attribute		046$c
<dateOther> with point="end"		046$d
<dateModified>		046$j
<dateValid> with point="start" or no point attribute		046$m
<dateValid> with point="end"		046$n
<copyrightDate>		260 $c [Generate a "c" before the date] (008/06="s")

<edition>		250 $a ind1=blank ind2=blank
<issuance> and		Leader/07
	value: continuing	Leader/07 (code s)
		[Note that some may be more appropriately mapped to "b" or "i"]
	value: monographic	Leader/07 (code m)
		[Note that some may be more appropriately mapped to "a"]
<frequency>		310 $a ind1=blank ind2=blank

language <language>
<language><languageTerm> with type="code" and authority="iso639-2b"		008/35-37
	additional languages add	041$a ind1=0 ind2=blank
			(repeat $a for multiple language codes)
<language> <languageTerm> with type="code" and authority="rfc3066"		041 $a and $2=rfc3066 ind1=0 ind2=7

physicalDescription <physicalDescription>
<digitalOrigin>="reformatted		007/11 CF (code a) with 007/00-10 (c\|\|\|\|\|\|\|\|\|)
	"digital"
<form authority="gmd">		245$h
<form authority="marcform">
	and value:
braille		008/23 BK, MU, SE, MM (code f) 008/29 MP, VM (code f)
electronic		008/23 BK, MU, SE, MM (code s) 008/29 MP, VM (code s) 008/26 CF (code m)
microfiche		008/23 BK, MU, SE, MM (code b) 008/29 MP, VM (code b)
microfilm		008/23 BK, MU, SE, MM (code a) 008/29 MP, VM (code a)
print		008/23 BK, MU, SE, MM (code blank) 008/29 MP, VM (code blank)
<extent>		300 $a ind1=blank ind2=blank
			except
		256 $a ind1=blank ind2=blank
				if
			form authority="marcform"
				followed by
			value "electronic"
				and
		<typeOfResource>="software, multimedia"
<internetMediaType>		856 $q
			append to 856 mapped from <identifier>
<reformattingQuality>
value: access		007/13CF code "a"
value: preservation		007/13CF code "p"
value: replacement		007/13CF code "r"

abstract <abstract>
<abstract> with		520 $a ind1=blank ind2=blank
	xlink:simpleLink="content"	520 $u

tableOfContents <tableOfContents>
<tableOfContents> with		505 $a ind1=0 ind2=blank
	xlink:simpleLink="content"	505 $u

targetAudience <targetAudience>
<targetAudience>			521 $a ind1=blank ind2=blank

<targetAudience authority="marctarget"				various positions
		and value:		008/22 BK, SE, CF, MU, VM
	adolescent			code "d"
	adult			code "e"
	general			code "g"
	juvenile			code "j"
	preschool			code "a"
	specialized			code "f"

note <note>
<note> with no type or uri attribute		500 $a ind1=blank ind2=blank
<note> with type=		5XX $a (a suggested list with mappings will be provided at a later date); if no appropriate specific field, use 500 $a
	appropriate name assigned, e.g.
	xlink:simpleLink="content"	856 $u
<note> with type=		511 $a
	"performers"
<note> with type=		518 $a
	"venue"
<note> with type=		245 $c
	"statement of responsibility"

subject <subject>
<subject authority="lcsh">		ind2=0
<subject authority="lcshac">		ind2=1
<subject authority="mesh">		ind2=2
<subject authority="csh">		ind2=3
<subject authority="nal">		ind2=5
<subject authority="rvm">		ind2=6
<subject authority="content">		ind2=7 if other value in authority; value in $2

Set 600, 610, 611, 650, 651 indicators based on <subject authority> attribute
First MODS subtag determines MARC tag:

<topic>		650 $a ind1=1
<name> with type="personal"		600 ind1=1 ind2 see above
<namePart>		600 $a
<namePart> with type="termsOfAddress"		600 $c [for titles associated with a name]
<role><roleTerm> with type="text"		600 $e
	"content"
<affiliation>		600 $u
<role><roleTerm> with type="code" and authority="marcrelator">		600 $4
	"content"

<name> with type="corporate"		610 ind1=2 ind2 see above
<namePart> (1st usage)		610 $a
<namePart> (each additional)		610 $b
<role><roleTerm> with type="text"		610 $e
	"content"
<role><roleTerm> with type="code" and authority="marcrelator"		610 $4
	"content"

<name> with type="conference"		611 ind1=2 ind2 see above
<namePart>		611 $a
<role><roleTerm> with type="code" and authority="marcrelator"		611 $4
	"content"

<title>		630 $a ind1=0
		if <nonSort> not present
		if <nonSort> is present
		ind1= number of characters in content
		ind2 see above
<partName>		630 $p
<partNumber>		630 $n

<geographic>		651 $a ind1=blank ind2 see above
<temporal>		650 $a
		Further subtags after the first in following subfields:
<topic>		$x in appropriate field based on first tag
<geographic>		$z in appropriate field based on first tag
<temporal>		$y in appropriate field based on first tag

<temporal> with encoding="iso8601"		045 $b ind1=0 ind2=blank
<temporal> with
	point="start" and encoding="iso8601"	045 $b ind1=2 ind2=blank
<temporal> with
	point="end" and encoding="iso8601"	045 repeat $b

<geographicCode> with authority="marcgac"		043 $a
<geographicCode> with authority="iso3166"		043 $c

<subject><hierarchicalGeographic>		752 ind1=blank ind2=blank
<country>		752 $a
<state>		752 $b
<county>		752 $c
<city>		752 $d

<subject><cartographics>		255 ind1=blank ind2=blank
<coordinates>		255 $c
<scale>		255 $a
<projection>		255 $b

<subject><occupation>		656 $a

classification <classification>
<classification> with authority="lcc"	050 $a ind1=blank ind2=0
	if
	<recordContentSource>="DLC"
	or
	"Library of Congress"
	else ind2=4
<classification> with authority="ddc"	082 $a ind1=0 ind=blank
and edition="content"	add $2
<classification> with authority="udc"	080 $a ind1=blank ind2=blank
<classification> with authority="nlm"	060 $a ind1=blank ind2=4
<classification> with authority="sudocs"	086 $a ind1=0 ind2=blank
<classification> with authority="candocs"	086 $a ind1=1 ind2=blank
<classification> with authority="content"	084 $a ind1=blank ind2=blank
	add $2

relatedItem <relatedItem>		Establish field using <relatedItem> type attribute:
<relatedItem> with no type specified		787 ind1=0 ind2=blank
<relatedItem> with type="preceding"		780 ind1=0 ind2=0
<relatedItem> with type="succeeding"		785 ind1=0 ind2=0
<relatedItem> with type="other format"		776 ind1=0 ind2=blank
<relatedItem> with type="original"		534 ind1=blank ind2=blank
<relatedItem> with type="host"		773 ind1=0 ind2=blank
<relatedItem> with type="constituent"		774 ind1=0 ind2=blank
<relatedItem> with type="otherVersion "		775 ind1=0 ind2=blank
<relatedItem> with type="series"		440 or 8XX (depending on name type)
		800 if <name> with type="personal"
		810 if <name> with type="corporate"
		811 if <name> with type="conference"
<relatedItem> with type="isReferencedBy"		510
<relatedItem> with displayLabel="content of subfield $i or $3"		76X-78X $i or 773 $3

title subelement:
<title> and		$t in 773, 774, 775, 776, 780, 785, 787, 534; $t in 800
	<partNumber>	$g in 774, 775, 776, 780, 785, 787, 534; $n in 440
	<partName>	$g in 774, 775, 776, 780, 785, 787, 534; $p in 440

<title> with no <titleInfo> type attribute and		787 $t
	<partNumber>	787 $g

<title> with <titleInfo> type="abbreviated" and		787 $p
	<partNumber>	787 $g

<title> with <titleInfo> type="uniform" and		787 $s
	<partNumber>	787 $g

name subelement:
<name> with type=personal"
	<namePart>	$a in 773, 774, 775, 776, 780, 785, 787, 534; $a in 800
	<namePart> with type="date"	append to data from first <namePart> in $a in 773, 774, 775, 776, 780, 785, 787, 534; $d in 800

	<namePart> with type="termsOfAddress"	800 $c [for titles associated with a name]
	<role><roleTerm> with type="text"	append to data after all instances of <namePart>, separated by comma in 773, 774, 775, 776, 780, 785, 787, 534; $e in 800
	<role><roleTerm> with type="code"	append to data after all instances of <namePart>, separated by comma in 773, 774, 775, 776, 780, 785, 787, 534; $4 in 800
<name> with type="corporate"
	<namePart>	append to data from first <namePart> in $a in 773, 774, 775, 776, 780, 785, 787, 534; 810$a (first instance) and 810$b (subsequent instances)
	<role><roleTerm> with type="text"	append to data after all instances of <namePart>, separated by comma in 773, 774, 775, 776, 780, 785, 787, 534; $e in 810
	<role><roleTerm> with type="code"	append to data after all instances of <namePart>, separated by comma in 773, 774, 775, 776, 780, 785, 787, 534; $4 in 810
<name> with type="conference"
	<namePart>	append to data from first <namePart> in $a in 773, 774, 775, 776, 780, 785, 787, 534; $a in 811
	<role><roleTerm> with type="code"	append to data after all instances of <namePart>, separated by comma in 773, 774, 775, 776, 780, 785, 787, 534; $4 in 811

<name> with no type attribute		787 $a

physical description subelement:
<physicalDescription>
<extent>		534 $e; $h in 773, 774, 775, 776, 780, 785, 787

note subelement:
<note>		$n in 773, 774, 775, 776, 780, 785, 787, 534

identifier subelement:
< identifier> with no type		$o in 773, 774, 775, 776, 780, 785, 787, 534
<identifier> with type="issn"		$x in 773, 774, 775, 776, 780, 785, 787, 534
< identifier> with type="isbn"		$z in 773, 774, 775, 776, 780, 785, 787, 534
<identifier> with type="uri"		856 $u ind2=2
< identifier> with type="local"		$w in 773, 774, 775, 776, 780, 785, 787, 534

part subelement
<part><text>		773 $g
<part> <detail><number> <extent><start>		773 $q [Generate a colon after each repeatable <detail> in numeric order] [Generate a less than angle bracket < (<) before <partExtent>]

identifier <identifier>
<identifier> with type="doi"	024 $a $2doi
<identifier> with type="hdl"	024 $a $2hdl
<identifier> with type="isbn"	020 $a ind1=blank ind2=blank
<identifier> with type="isbn" and invalid="yes"	020 $z ind1=blank ind2=blank
<identifier> with type="isrc"	024 $a ind1=0 ind2=blank
<identifier> with type="isrc" and invalid="yes"	024 $z ind1=0 ind2=blank
<identifier> with type="ismn"	024 $a ind1=2 ind2=blank
<identifier> with type="ismn" and invalid="yes"	024 $z ind1=2 ind2=blank
<identifier> with type="issn"	022 $a ind1=blank ind2=blank
<identifier> with type="issn" and invalid="yes"	022 $z ind1=blank ind2=blank
<identifier> with type="issue number"	028 $a ind1=0 ind2=0
<identifier> with type="lccn"	010 $a ind1=blank ind2=blank
<identifier> with type="lccn" and invalid="yes"	010 $z ind1=blank ind2=blank
<identifier> with type="matrix number"	028 $a ind1=1 ind2=0
<identifier> with type="music publisher"	028 $a ind1=3 ind2=0
<identifier> with type="music plate"	028 $a ind1=2 ind2=0
<identifier> with type="sici"	024 $a ind1=4 ind2=blank
<identifier> with type="sici" and invalid="yes"	024 $z ind1=4 ind2=blank
<identifier> with type="stocknumber"	037 $a ind1=blank ind2=blank
<identifier> with type="uri"	856 $u ind1=blank ind2=blank
<identifier> with type="uri" and attribute	856 $3
<identifier> with type="upc"	024 $a ind1=1 ind2=blank
<identifier> with type="upc" and invalid="yes"	024 $z ind1=1 ind2=blank
<identifier> with type="videorecording	028 ind1=4 $a ind2=0

location <location>
	<physicalLocation>	852 $a
	<physicalLocation> with displayLabel="content"	852 $3
	<url>	856 $u
	<url> with displayLabel="content"	856 $3
	<url> with dateLastAccessed="Last accessed: Content"	856 $z

accessCondition <accessCondition>
with type="restrictionOnAccess"	506 $a ind1=blank ind2=blank
with type="useAndReproduction"	540 $a ind1=blank ind2=blank

extension <extension>	887 $a ind1=blank ind2=blank
		with $2="mods"
	[Include XML syntax with content]

recordInfo
<recordContentSource> with		040$a
	authority="marcorg"
<recordCreationDate> with		008/00-05
	encoding="marc"
<recordChangeDate> with "		005
	encoding="iso8601
<recordIdentifier>		001
attribute source		003
<languageOfCataloging> and <languageTerm> with		040 $b
	authority="iso639-2b"

4. Leader and Fixed Fields

A MARC 21 record requires a Leader and field 008 (Fixed-Length Data Elements). Certain character positions in each of these fixed-length fields will need coding, although most will generate default values.

Leader -- Data elements that provide information for the processing of the record. The data elements contain numbers or coded values and are identified by relative character position. The Leader is fixed in length at 24 character positions (00-23) and is the first field of a MARC 21 record. Converted records should include a Leader as follows:

00-04 - Logical record length
	computer-generated, five-character numeric string
05 - Record status
	set to "n" (new)
06 - Type of record
	see above under <typeOfResource>
	if none indicated set to "a" (language material)
07 - Bibliographic level
	if <originInfo><issuance>="monographic, set to "m" (monograph/item)
	if <originInfo><issuance>="continuing", set to "s" (serial)
	if <typeOfResource> with attribute "collection=yes", set to "c" (collection)
Only one value may be used; if more than one of the above values is in a MODS record, consider this in priority order; if none of these values are indicated, set to "m"
08 - Type of control
	set to "blank"
09 - Character coding scheme
	set to "blank"
10 - Indicator count
	set to "2"
11 - Subfield code count
	set to "2"
12-16 - Base address of data
	computer-generated five-character numeric string
17 - Encoding level
	set to "u"
18 - Descriptive cataloging form
	set to "u"
19 - Linked record requirement
	set to "blank"
20-23 - Entry map
	set to "4500"

008: Fixed-length data elements
Establish appropriate 008 according to <typeOfResource> as indicated above. Fill in character positions as follows:

008/00-05 - Date entered on file
	-- see <recordInformation> <recordCreationDate encoding="marc">
	-- if not present, generate a six-character numeric string representing the day the MARC 21 record was created using the following format: yymmdd.
008/06 - Type of date/publication status
	-- if <originInfo><issuance="monographic"> and <dateIssued> is not repeated, set to "s" (single known date/probable date)
	-- if <originInfo><issuance="monographic"> and <dateIssued point="start">, set to "m" (multiple dates)
	-- if <originInfo><issuance="monographic"> and <dateIssued point="end">, set to "m" (multiple dates)
	-- if <originInfo><issuance="continuing"> and <dateIssued point="end" encoding="marc">=9999, set to "c" (continuing resource currently published)
	-- if <originInfo><issuance>="continuing" and <dateIssued point="end" encoding="marc">=[some date], set to "d" (continuing resource ceased publication)
	-- if <originInfo><issuance="continuing"> and <dateIssued point="end" encoding="marc">=uuuu, set to "u" (continuing status status unknown)
	-- if <originInfo> includes <dateIssued> without <issuance>, set to "s" (single known date/probable date)
	-- if <originInfo> includes <dateIssued encoding="marc">, set to "s" (single known date/probable date)
	-- if no data in <dateIssued>, set to fill (\|)
008/07-14 - Date 1/Date 2
	-- see above under <originInfo><dateIssued>
	-- if no data, set to fills (\|)
008/15-17 - Place of publication, production, or execution
	-- see above under <originInfo><place><placeTerm type="code authority="marccountry">
008/18-34
	-- set as specified above under <genre> and <targetAudience>
	-- set unused character positions to fills (\|)
008/38-39
	--set to fills (\|)

5. Changes Made for MODS Version 3.0

--Replaced all occurrences<role><text> with <role><roleTerm type="text">
--Replaced all occurrences<role><code> with <role><roleTerm type="code">
--Replaced all occurrences<place><text> with <place><placeTerm type="text">
--Replaced all occurrences<place><code> with <place><placeTerm type="code">
--Replaced all occurrences<language><code> with <language><languageTerm type="code">

name
--Added <namePart type="termsOfAddress"> under 100, 700 $c

typeOfResource
--Added value "sound recording--nonmusical" under Ldr/06 value i
--Added value "sound recording--musical" under Ldr/06 value j

originInfo
--Added <dateModified> under 046 $j
--Added <dateCreated point="start"> or no point attribute under 046 $k
--Added <dateCreated point="end"> under 046 $l
--Added <dateValid point="start"> or no point attribute under 046 $m
--Added <dateValid point="end"> under 046 $n
--Added <copyrightDate encoding="marc"> under 008/11-14 if 008/06=t
--Added <dateIssued qualifier="questionable" point="start" encoding="marc"> under 008/07-10 if 008/06=q
--Added <dateIssued qualifier="questionable" point="end" encoding="marc"> under 008/11-14 if 008/06=q

physicalDescription
--Deleted <controlled> and <unControlled> subelements

subject
--Added <geographicCode authority="marcgac"> under 043 $a
--Added <geographicCode authority="iso3166"> under 043 $c
-- Added <namePart type="termsOfAddress"> under 600 $c
--Added <occupation> under 656 $a

relatedItem
-- Added <namePart type="termsOfAddress"> under 700, 800 $c
--Added <relatedItem displayLabel="contents of subfield $i"> under 76X-78X $i
--Added <relatedItem displayLabel="contents of subfield $3"> under 773 $3
--Deleted <relatedItem type="related">
--Added <part><text> under 773 $g
--Added <part><detail order="1"><number><detail order="2"><number><detail order="3"><number><partExtent><start> under 773 $q
--Added <relatedItem type="isReferencedBy"> under 510

location
--Added <location><physicalLocation> under 852 $a
--Added <location><physicalLocation displayLabel="contents of subfield"> under 852 $3
--Added <location><url> under 856 $u
--Added <location><url displayLabel="contents of subfield"> under 856 $3

recordInformation
--Added <recordContentSource authority="marcorg"> under 040 $a

Questions and comments:

Library of Congress Help Desk ( 02/25/2004 )

MODS to MARC 21 Mapping Version 3.0