Introduce Field lets you specify where the field should be initialized. If the current editor file is an NUnit [TestFixture] class, it would be extremely helpful to have an additional option for this: initialize the field in the test [SetUp] method. Ideally, this option would be selected by default whenever Introduce Field is used inside a test class. It could even replace the "Field declaration" and "Constructor(s)" options, as neither of those typically makes any sense for a test class.