 <p>Following are the under Microsoft Public License (Ms-PL) license and You might want to check out <a href="http://www.codeplex.com/quickgraph" rel="nofollow">QuickGraph</a>.</p></p> <p><a href="http://www.codeplex.com/NodeXL" rel="nofollow">NodeXL</a> might also be of interest (visualization library). It's WPF, but you can use a container to host it if you need WinForms.</p> <p>You can use check <a href="http://www.graphviz.org/" rel="nofollow">GraphViz</a> to generate this sort of graph. My app generates the <strong>.dot</strong> file that can then is then passed into GraphViz. It supports a load of file formats, such as bmp, jpg, png, pdf, svg etc etc.</p> <p>Reference:</p> <p><a href="http://www.dmoz.org/Science/Math/Combinatorics/Software/Graph_Drawing/" rel="nofollow">Open Source tools list</a><br> <a href="http://stackoverflow.com/questions/737771/c-sharp-graph-drawing-library">C# graph drawing library?</a><br> <a href="http://stackoverflow.com/questions/69275/drawing-a-web-graph">Drawing a Web Graph</a></p> <p>You could use <a href="http://quickgraph.codeplex.com/" rel="nofollow">QuickGraph</a> to easily model the graph programatically, then export it to <a href="http://quickgraph.codeplex.com/wikipage?title=Visualization%20Using%20Graphviz&amp;referringTitle=Documentation" rel="nofollow" >GraphViz</a> or <a href="http://quickgraph.codeplex.com/wikipage?title=Visualization%20Using%20Glee&amp;referringTitle=Documentation" rel="nofollow" >GLEE</a>, then render it to PNG.</p>