If you mean "can I recompile only page 3 and 4 out of my 100-page book and get the whole document" that answer is no I think. But there are other ways.
I suspected.
Well, you also have texmfstart newtexexec.rb --pfdcombine | copy | select | trim I don't know how exactly to use them (to hans: lines 351-359 in newtexexec.rb, "def copyortrim" seem to be broken a bit - wrong number of arguments), but I guess that you could combine parts of your document together again this way (I wouldn't use this approach however). But what's wrong with using modular approach (to compile just the chapter or section you're currently working on, so that it compiles fast enough and you can fix bugs, and then compile everything together when you need the whole document)? You don't need to change a single line if you compile separate chapters or if you compile everything together. Except that you might need to split the document in separate files (using projects/products is really a great thing). If you don't want to split your document, you can also use modes: \starttext \startmode[everything] \enablemode[chapter1] \enablemode[chapter2] \stopmode \chapter{Introduction} \startmode[chapter1] \chapter{Chapter A} \stopmode \startmode[chapter2] \chapter{Chapter B} \stopmode \stoptext Then you can compile the document with texexec --mode=chapter1 filename or texexec --mode=chapter1,chapter2 filename or texexec --mode=everything filename Mojca