Its part of the certification standard for both FAA and JAR certified aircraft.
There will be maint checks required afterwards depending on the type these can be extensive or a 5 min job depending on the flight parameters recorded on touchdown. Heavy aircraft your looking at shagged gear and tyres and TP's the gingers boot the tyres have a look for leaks while sorting out the reason why you have landed in the first place.
Its not something to be taken lightly but you are not going to be circling burning off fuel for 30 mins to get under MLW with an uncontained engine fire.
Loosing an engine then securing it with no other issues wouldn't be a valid excuse to immediately land. But if there were other issues which were coming into play for example the wx was coming in, other systems were dropping out, there wasn't a clear cut reason why the first engine shut down so fuel contamination was suspected you get the bird on the deck. It all comes down to the PIC's risk assement of staying in the air V over max weight landing.
Here is a thread in the tech form by chaps that are way way more experenced than myself
http://www.pprune.org/tech-log/27392...necessary.html