There are a couple (maybe a few) different types of activity that can be added to a case. Mostly they're just specializations of the generic form of adding a "memo" or unstructured, non-milestone activity.

*Unstructured comment - non-milestone activity
*Structured comment - milestone activity
*Classification - case review
*Referral

Name: Add an activity to a case

Identifier: UC 03

Basic course of action

• User locates an existing case (insert link to that use case)
• User creates a new activity
  • System asks user to choose an activity type
  • User chooses an activity type
  • SCENARIO: the selected activity type has custom fields
    • system prompts user to supply values for the custom fields
    • user supplies the required values for the custom fields
  • SCENARIO: the selected activity type has no custom fields
    • proceeds just as it would for creating any other CiviCRM activity
  • System associates the activity with the case (in both scenarios)
• User saves the activity.
  • THOUGHT: if we're going to go through with our plan to make activities read-only once saved, we may want to force a preview of every activity prior to saving.  This will allow users to verify that everything is as they want it before committing to a save.
• System shows the current activity at the top of the list of activities associated with the case
• User verifies that the activity has been stored.