With SMF, you can have separate permissions for each board, so that different groups can do different things on different boards. This can be useful for a board that you want users to be able to reply to posts in, but not post new topics.

First you need to enable local permissions, by going to Admin>Permissions>Settings and selecting "Enable advanced by-board permissions".

You can set the board to use local permissions, under the "Permissions by board" tab. Click on the board name to add the permissions for each group, or change them. These permissions will only apply to this one, particular, board. For each board that requires custom permissions, you would need to set them, manually and apply to each board.

With SMF v2.x, you need to go to Admin>Permissions>Edit Profiles>Add new name to create the profile and edit it. You can, then, assign it to a board when you edit the board.

For SMF v2.x, you can re-use a permission profile on multiple boards.

There are some pre-defined profiles available, which you can see in SMF v1.x, when you edit the boards permissions in the drop down "Apply Pre-Defined Permission Profile". In SMF v2.x, they are shown when you go to Admin>Permissions>Edit Profiles. You can not change those permissions, though, as they are the default profiles. These pre-defined profiles do not include permissions for any mods that you may have installed. So, you should verify that the permissions are correct. It may be easier to create a custom profile, instead of using a pre-defined one, because you can be more certain as to what permissions are given to your members.