Continual Queries (CQs) allow users to receive new information as it becomes available. CQsystems need to support a large number of CQs due to the scale of the Internet. One approach to this problem is to group CQs so that they share their computation on the assumption that many CQs have similar structure. Grouping queries optimizes the evaluation of the queries by executing common operations in the group of queries just once. However, traditional grouping techniques are not suitable for CQs because their grouping raises new issues. In this paper we propose a scalable and dynamic CQgrouping technique. Our grouping strategy is incremental in that it scales to a large number of queries. It also re-groups existing grouped queries dynamically to maintain the effectiveness of the groups.