Hi Folks, I apologize for not answering the original messages properly, I had mail deliver disabled, so I can't. I have enabled it, so I'll answer properly from now on. To Hillarie: If you don't use Polymorph, but want to build your own Morphs from scratch, SimpleMorphic is simpler, easier to understand, tweak and fix. To Doru: Let's do a comparison: Size of 4 core classes (Morph, MorphExtension, PasteUpMorph and WorldState) Pharo / Squeak / Cuis totalIvars: 39 / 46 / 26 totalClassVars: 15 / 10 / 5 totalInstMethods: 1170 / 1764 / 663 totalClassMethods: 55 / 71 / 16 Size of the whole Morph hierarchy Pharo / Squeak / Cuis totalClasses: 197 / 331 / 58 totalIvars: 649 / 1063 / 257 totalClassVars: 54 / 138 / 28 totalInstMethods: 6651 / 9186 / 2115 totalClassMethods: 303 / 858 / 127 SimpleMorphic is much smaller. Core classes are simpler and easier to understand, fix and extend. The most important part is that this is not blind removal of unused code. A lot of the functionality has been redesigned to make it simpler, and the removal was done with great care to result in a consistent system. This work started in 2004, so we're talking of about 6 years of careful work. All this means that SimpleMorphic does not support all the features that Pharo or Squeak might support. Please use the browsers and other tools in Cuis to check what it indeed can do. Talking about complexity, let's take for example, morph layout. This is started with #doLayoutIn: in Pharo and #doLayoutIfNeeded in SimpleMorphic. In Pharo, this method calls #adjustLayoutBounds: (19), #layout:in: (149), #layoutProportionallyIn: (10), #computeCellArrangement:in:horizontal:target: (87), #computeGlobalCellArrangement:in:horizontal:wrap:spacing: (31), #computeCellSizes:in:horizontal: (30), #computeExtraSpacing:in:horizontal:target: (136), #layoutLeftToRight:in: (91), #layoutTopToBottom:in: (91), #placeCells:in:horizontal:target: (70). The numbers in parenthesis are the sum of the lines of code of the implementors. Total lines of code for layout (taking only these most important methods) is 714. I doubt there are many people who really understand all of this code. In SimpleMorphic (Cuis), this calls #layoutSubmorphsIn: (10), #applyLayoutFrameIn: (11), #layout:in: (24). Total lines of code is 45. I believe any smalltalker could understand these in just minutes. I hope this makes makes it clearer to you what SimpleMorphic is. Cheers, Juan Vuletich