This is a proposition of a schema that can be used to accommodate all the data needed for the previously listed functions. It should under no circumstances be regarded as authoritative. It is an example that should serve it's purpose, but it is likely you have to adapt it to match your specific needs. Because it has been a lot of work (for me, maybe it's out there but I don't know where?) to find out the specific meaning of each entry, and what information it should contain, I'll try to do this as well. It should be noted, however, that it doesn't fit together seamlessly. The Microsoft Addressbook does not seem to use some of the fields it is presenting. I suspect that for the "Title", "Nickname", "Home City", "Home State/Province", "Home ZIP Code", "Home Country/Region" and "Home Web Page" entries no information is requested. For the "Personal", "Netmeeting" and "Digital IDs" I didn't yet bother to figure out how it should be put in the Ldap database. Any information is welcome. The netscape address book has a similar problem. When a record is copied from an LDap directory to a local address book, some of the fields are lost. As the nature of an company-wide addressbook should discourage users to copy addresses locally, this is not a big problem though. But netscape address book has another little oddity though. In a normal address record, the Ldap attribute associated with "Nickname" is xmozillanickname. When searching for addresses however, the associated attribute is simple nickname. That is the reason why the nickname entry shows up twice in the schema. This schema is known to work with Microsoft Outlook 2000, and Netscape 4.73. If you find I'm wrong about a description, function, or neccessity of an entry, please do let me know! The schema file that represent this schema can be found in . Function Objectclass Attributes Description (Default) valueUser accounts top default ou Organizational Unit Usersperson Owner is a person uid unix login name foocn Common Name Foo Barsn Surname Baraccount Owner has an account posixaccount Owner has a Unix account uidNumber uid 513gidNumber gid 100homedirectory Home directory /home/users/foouserpassword unix password S3cr3tsambaaccount Owner has a samba account ntuid Unknown uidrid Unknown uidnumberlmpassword Lanman password hash Unusedntpasswd NT password hash Unusedloginshell Users shell /bin/pleuropMachine accounts top default ou Organizational Unit Machinesposixaccount Owner has a unix account uid login name speed$uidnumber unix uid 514gidnumber gid 100homedirectory Home directory UnusedMicrosoft Address Book top default ou Organizational Unit Addressbookmicrosoftaddressbook Owner has Microsofts Addressbook properties cn Name c Business country department Business department facsimiletelephonenumber Business fax number givenname First name homephone Home phone number homepostaladdress Home postal address info Notes initials Initials l Business city mail Email address mobile Home cellphone number organizationname Company name otherfacsimiletelephonenumber Home fax number otherpager Business pager number can be "pager" too?physicaldeliveryofficename Location of office at work postaladdress Business postal address postalcode Business postal code sn Last Name st Business state/province telephonenumber Business phone number title Job title url Business web page Netscape Address Book top default ou Organizational Unit Addressbooknetscapeaddressbook Owner has Netscape's properties cn Name cellphone Cellphone number countryname Country description Description facsimiletelephonenumber Fax number givenname First Name homephone Home phone number homeurl Personal web page locality Home city mail Email address nickname Nickname o Company ou Department pagerphone Pager number postalcode Home postal code sn Last name st State streetaddress Home postal address telephonenumber Business phone number title Title xmozillaanyphone Business phone number xmozillanickname Nickname Same as nicknamexmozillausehtmlmail Client uses html mail TRUENetscape roaming access top default ou Organizational Unit Roaming Netscape and Microsoft use the addressbook entries in a slightly different way. Netscape stores a postal address in the streetaddress entry in a base64 encoded string, while Microsoft uses the postaladdress entry. However, when a streetaddress entry is present, Microsoft uses this instead of the postaladdress entry, but it's value is stored plaintext, not base64 encoded. So you cannot use them at the same time. More information about Ldap schema's in general can be found on Linux Center. I found a document describing Microsoft Addressbook's properties on the Microsoft Developers Network. Beware, the description given on the Microsoft page doesn't match the fields where the content shows up in address book. Also, not all fields in address book contain information, but if the listed keys don't work I wouldn't know which keys do work.