The traditional paradigm for managing memory in database management systems (DBMS) treats memory used for caching table data and memory for temporary data as separate entities. This leads to inefficient utilization of the available memory capacity for mixed workloads. With memory being a significant factor in the costs of operating a DBMS, utilizing memory as efficiently as possible is highly desirable. As an alternative to the traditional paradigm, we propose managing the entire available memory in a cooperative manner to achieve better memory utilization and consequently higher cost–effectiveness for DBMSs. Initial experimental evaluation of cooperative memory management using a prototype implementation shows promising results and leads to several interesting further research directions.