How to restrict SSH access

Hi everybody,
I’m currently enabled every hosting account to use SSH. But how can I restrict them to manipulate with their folders only (example account1 can access to /home/account1 only, account2 access to /home/account2 only) and not other folder of whole system like /
Of course it’s configured to not allow access to sensitive data like configuration file, but restrict to only their folder will be great and safer.

Thank you.