UPDATE rows based on multiple WHERE values?

[Waynn Lue]

Is there any way to have an UPDATE statement change a column value based on
the WHERE statement?

Essentially, I want to do something like this

UPDATE Actions SET ActionsSent = <foo> WHERE ActionsReceived = <bar>

where foo and bar change for multiple sets of values.  Is there a way to do
this in one SQL statement, or do I have to execute an UPDATE statement per
pair of values?

Thanks,
Waynn