Both the K1100 and K1200 edition of the the KACE appliances provide you the ability to more granularly define roles. Roles can define what tabs are accessible and whether that access is "read-only" or full "write" access.
You can create Roles in your K1000 appliance specifically for each Organization In the Roles sub-tab of the Helpdesk (http://k1000/adminui/user_role_list.php)
If you have a K1200 then you have access to Organizations. Roles and their access are uniquely defined within each Organization. For convenience you might want to have some cross-organization accounts. To define these simply create the same account within each organization (same username and password) and you will be able to switch Organizations more seamlessly and the K1000 appliance will automatically attempt to log you in to each organization as you switch.
After you have defined a role you can assign users to be in a Role by editing your users in the User sub-tab of the Helpdesk tab (http://k1000/adminui/user_list.php)
More information can be found in the Administrator Guide under "Creating and Editing Roles".