Question: I have a requirement to document the assembly dependencies in a vb6/dotnet application.

What techniques / tools are good for performing this sort of document.

I was planning on using Visio for drawing.

Answer: 
Well for .NET you could also try VS2010 Beta 1 and the Architecture Explorer [(Arch Explorer screen shots)](http://ajdotnet.wordpress.com/2009/03/29/visual-studio-2010-architecture-edition/).

As for VB6, I'd like to have a tool for that also. This tool from Microsoft [Visual Basic 6.0 to Visual Basic .NET Upgrade Assessment Tool](http://www.microsoft.com/downloads/details.aspx?FamilyId=10C491A2-FC67-4509-BC10-60C5C039A272&displaylang=en) creates a call graph in HTML for a single VBP, not sure how useful it would for you. Other than that I have not found may tools for VB6.
You can create dependency graphs of .NET assemblies and application projects in VS 2010 Ultimate. You can generate assembly dependency graphs as one of the standard graphs, or you can use Architecture Explorer to browse your solution, select projects and the relationships that you want to visualize, and then create a dependency graph from your selection.

For more info, see the following topics:

**How to: Generate Graph Documents from Code**: <http://msdn.microsoft.com/en-us/library/dd409453%28VS.100%29.aspx#SeeSpecificSource>

**How to: Find Code Using Architecture Explorer**: <http://msdn.microsoft.com/en-us/library/dd409431%28VS.100%29.aspx>

**RC download**: <http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=457bab91-5eb2-4b36-b0f4-d6f34683c62a>.

**Visual Studio 2010 Architectural Discovery & Modeling Tools** forum: <http://social.msdn.microsoft.com/Forums/en-US/vsarch/threads>