» OMG UML Resource Page
   Object Management Group (OMG) provides the newest UML standards, add-ons and features on their site.
   http://www.uml.org/

» An UML Open Directory
   An Open Directory for Unified Modeling Language community (Powered by Visual Paradigm).
   http://directory.visual-paradigm.com/

» Cetus Links on UML
   Collection of links; includes other links on objects and components.
   http://www.cetus-links.org/oo_uml.html

» Free UML CASE tool and OO Resource Page
   Links on Free Object Oriented Unified Modeling Language tools, links, and resources.
   http://www.angelfire.com/space/umltutor/

» Ivar Jacobson's postcards
   Dr. Ivar Jacobson is one of the fathers of use cases, the Unified Modeling Language and the Rational Unified Process. His postcards contains his recent impressions, thoughts and reflections.
   http://www.jaczone.com/postcards/

» Klasse Objecten
   Specialized in consultancy and training in UML, OCL, Unified Modeling language, Object Constraint Language, object technology and component based development.
   http://www.klasse.nl/

» Model Driven Development Executable and Translatable UML
   xtUML is a model-driven development process based on industry-standard UML notations. xtUML models are executed and tested early in the development lifecycle and are translated to generate optimized target code.
   http://www.projtech.com

» Objects by Design
   Covers recent developments in object-oriented design and programming. Includes list of books, UML modeling tools, projects and forums.
   http://www.objectsbydesign.com/

» The Precise UML Group
   Publications, events, mailing list, links and organization; working on the evolution and standardization of the Unified Modeling Language.
   http://www.cs.york.ac.uk/puml/

» The UML Bibliography
   Contains references to publications and links about the Unified Modeling Language.
   http://www.db.informatik.uni-bremen.de/umlbib/

» UML Diagram Gallery
   A collection of UML diagrams sample, resources, tips and tricks for applying UML in software development projects.
   http://www.visual-paradigm.com/VPGallery/index.html

» UML Links by Prashant N. Mhatre
   Important links on UML.
   http://www.onesmartclick.com/programming/unified-modeling-language.html

» UML Resource Center
   The Unified Modeling Language industry-standard for specifying, visualizing, constructing, and documenting the artifacts of software systems. By Rational Software Corporation.
   http://www-306.ibm.com/software/rational/uml/

» UML Resources
   Unified Modeling Language resources, related links, tutoirals and tools.
   http://www.geocities.com/kevinlerdorf2002/casetool.html

» Use Case Maps
   News, tools, publications and links. Includes information on the UCM User Group.
   http://jucmnav.softwareengineering.ca/twiki/bin/view/UCM/WebHome

» VisualBuilder.com UML Tutorial
   Intro to UML focusing on Use case and Class diagrams.
   http://www.visualbuilder.com/uml/tutorial/