When SQL Server executes a query, memory is required to store temporary data while rows are sorted or joined. This memory grant is controlled by the resource semaphore to avoid that a query monopolizes the whole memory for itself and thus all other queries must wait for their memory allocation. In this session, we will cover the different memory grants and its DOP and server memory dependency, the impact of the resource governor, spilling into tempdb as a result of missing memory, and finally the functionality of the memory grant feedback feature, which was introduced in SQL Server 2019. Thereby, we will also learn how to identify and optimize memory intensive queries to increase overall throughput.