If you send your work to client and you don't want that the can edit it or print it, before the have paid, here is a solution.
Save your image as a .PDF and secure it with a password.
Go to File > Save and choose Photoshop PDF and hit the 'Save' button.
Then go the security. Here you can choose for the option to add a password. So hit the checkbox, add the password and click on 'Save PDF'
And have you already discovered our Facebook page Humans of the Nordic Region?