SSMS 18.x installs side by side with previous versions, so both versions are available for use.
The SSMS 18.x installation doesn’t upgrade or replace SSMS versions 17.x or earlier. SSMS combines a broad group of graphical tools with a number of rich script editors to provide developers and administrators of all skill levels access to SQL Server. SQL Server Management Studio (SSMS) is an integrated environment for accessing, configuring, managing, administering, and developing all components of SQL Server.
