It is all over the globe, doing everything.
It may also have turned a blind eye to fight clubs, drug deals, and cellphone and internet usage among inmates at Auckland's Mt Eden prison, which it ran on behalf of we taxpayers.
Serco has done what Ernst Stavro Blofeld, the Decepticons, the Daleks and Donald Trump could not. World Domination.
The trouble with WD is that it's a tricky, messy, 24-hour business. You sort one bit out and another bit goes pear-shaped. Basically, it is not all it is cracked up to be.
In the case of the New Zealand prison scandal, and in many other facets of its work, it is doing what governments should be doing. There is meant to be proper oversight and accountability on behalf of the citizens who are paying for these services but with Serco self-reporting any problems at Mt Eden (or possibly not reporting), this notion is in serious doubt.
Perhaps the issue is that governments are run by former financial traders and free-marketeers who are overly admiring of the profit-before-people entrepreneurship demonstrated by Serco.