I had the same question and came to the following solution. The component files begin as follows: \startcomponent extreme-cases \product book \project project \startnotmode[*product] \environment env_book \stopnotmode ... Here, env_book.tex is the product-specific environment file, which is called at the beginning of the product file book.tex. If only a component is being run, the \startnotmode[*product] will ensure that env_book is read in anyway. Let me know if that does what you want (CC me as well as the list, since I'm highly irregular in reading list email these days, due to having a baby, and might miss your response otherwise). -Sanjoy "Creativity can be a social contribution, but only in so far as society is free to use the results." --Richard Stallman