Thank you, Matthias and Wolfgang, for the examples/solutions. If I understand them right, there must be one solution for each exercise (otherwise the solution numbering gets out of sync). Or do the coupling= options in Matthias's example remove that restriction? In my experiments with the examples, deleting the first solution unsynchronized the exercise--solution numbering, no matter how I fiddled with the coupling keys. In the ideal pedagogical world, I'd write a solution for each exercise. But reality might intervene, so I still wonder if the solutions can automatically know and include the exercise number (perhaps by placing \startanswer..\stopanswer inside \startexercise..\stopexercise and using \getnumber[exercise]). If there is a clever way, that's great. But, the nature of TeX as a macro language may preclude the \getnumber code being evaluated just when one wants. Regards, -Sanjoy