I think that this is advisable when you're making a dramatic change, such as going to graduate school, where the nature of that change is such that your departu

I think that this is advisable when you're making a dramatic change, such as going to graduate school, where the nature of that change is such that your departure can't be taken to reflect on the company that you're leaving. If it's April, and you accept an offer to attend graduate school in September, it's probably best to let your boss know as soon as you've made the decision. If you are moving to another company, then it's touchier because it raises questions about why you want to work at Y instead of X, and I think the 2 weeks' notice and generic exit interview are the better approach. There's nothing you gain by saying the reason you'd rather work at Y.