Why do i not see the IsChanged function

Motty, 

The function should be there but be sure that you do not use the 'Every time a record is created or edited' Run Time. This will no longer work with IsChanged() by design as it caused some issues on the back end specifically around creating loops that would cause many errors and performance issues. You will need to use 'When a record is created, or when a record is edited and did not previously meet the rule criteria'. 

As for not seeing the function, you should see it, note my attached screen capture. If you see something different provide a screen capture. 

Sincerely,

Boris

Sorry to add to this after such a long time, but I'm having the same problem, but I'm getting exactly the opposite behavior to the reply given.

When I chose the 'Every time a record is created or edited' option I can select the IsChanged function. When I choose the 'When a record is created, or when a record is edited and did not previously meet the rule criteria' option, it isn't available. The same thing happens with the GetPreviousValue function which I thought I could use as a work around.

I would use the 'Every time a record is created or edited' option, but if I select that it doesn't allow me to choose the New Item or Delete item action!

At the moment it seems like the system is doing its best to stop me doing what I want to do. AAArrgh!

Hi Andrew. For Workflow Rules IsChanged() is available for "Only when a record is created," "Every time a record is created or edited," and "Every time a record is deleted." You might have to create more than one rule for the use case.