Approach Climb/Landing Climb in Engine out situation

[Empty Cruise]

It's pretty simple - you must always have a 'way out', unless we're talking an emergency where the crew have deemed that a missed approach is not an option and that the aircraft will be landed - or 'landed' - no matter what.

So - when deciding to make an overweight landing, the CDR have to satisfy themself that the aircraft can either a) stop on the available runway or b) execute a missed approach. When you're able to execute either option, you're ready for the approach.