If you are managing multiple projects, you might want to move users around and add your users to some project. Here is how you can add existing user(s) to a project. 

1. Go to "Manage" tab and select "Manage Projects". Then choose a specific project to edit. Then select the "Users" tab on the left. ( Figure 1 )

 Figure 1 

2. Click the text field for selecting users, you will see a drop down list that shows your users that are not in the current project yet. ( Figure 2 )

 Figure 2 

 Figure 2 

 Figure 2 

3. Select one or more users so that they show in the text field. Click "Add User(s) to this Project" button. Then the users will be appended to the bottom of the list. Here you can assign role to the added project (the default role is Member). ( Figure 3  and  Figure 4 )

 Figure 3 

 Figure 4 

4. Click "Save Changes" button to add the new user(s) to the projects. Then you will see a notification message about the project information being updated successfully. ( Figure 5 )

Important -- Please note that you have to click "Save Changes" to commit the action. 

 Figure 5