Hi Azadeh, First, you have to create nodes to be able to draw edges. Second, in your case, I guess the simplest thing is to use the numbers as the models for the edges and just specify "from:" from the first collection and "to:" from the second collection. Perhaps something like this would work: viewFrom: col1 to: col2 | view | view := Mondrian.ViewRenderer new. view node: col1 forIt: [ view nodes: col1. view verticalLineLayout.]. view node: col2 forIt: [ view nodes: col2. view verticalLineLayout.]. "we just created 2 nodes for the two collections and inside we added a node for each element" "we also laid out the nodes vertically inside each root node" view edges: (1 to: col1 size) from: [:index | col1 at: index] to: [:index | col2 at: index]. view open Cheers, Doru On Jun 3, 2008, at 7:09 PM, azadeh wrote: -- www.tudorgirba.com www.tudorgirba.com/blog "Every successful trip needs a suitable vehicle."