Hi, As it seems that the eUML syntax suggested by Robert Stewart is favored by most of those who gave their opinion about it, I decided to give it a try and uploaded into the vault (http://www.boostpro.com/vault/index.php?direction=0&order=&directory=Msm&) a preview version (review_tests.zip) of the new syntax, along with 3 tutorials rewritten using this new syntax. This will allow us to play with it and see if we like it. I'd be happy to get some feedback. I personally found it hard to get used to this syntax, but it can be because I'm so used to the "old" one. Another effect is that I had to reorganize my transitions based on the target state instead of the source, which made me change my debug state_name array (as written in Annex A, the index of a state is based on its position in the transition table). If you don't use state names as debug information, you needn't mind about it. Tested compilers were VC9 and g++ 4.3. Please post your comments in the developer list. Have fun! Christophe PS: a few speed optimizations (due to interesting tests from Barend Gehrels) are also in, so should the back-end make any problem, please let me know.