Variable Subsets allow you to create subsets of answer-alternatives. For instance if you are doing a multi-country project that has a large general brand list. Some of those brands might only be available in Sweden for instance. You can then create variable subsets of those brands. By carefully managing access you can make sure those subsets are only shown for the Swedish market. Perhaps you have a series of Questions which was only asked from the UK sample? By turning those questions into a subset they will only be shown for the UK reports.