Of Wikipedia and vandalism.

Wikipedia is regarded as a bastion of factual accuracy and impartiality.

If you have no idea what Wikipedia is, please step blinking into the sun and let me explain:
It's an online encyclopaedia that anyone can contribute to. Literally anyone. There are no pre-requisites, no background checks and exactly one hoop to jump through: bothering to post the edits.

Fantastic idea isn't it? A platform for the entirety of human knowledge to be collected in a single shining pantheon, stripped of journalistic bias and sensationalism, and laid bare for all to marvel at. Enshrining almost 60 times more information that the Encyclopaedia Britannica. A beacon of knowledge and wisdom through collaboration and communal spirit!

Except this is the internet, a place which at times can be a wretched hive of scum and villainy™.

From Wikipedia:

Vandalism is any addition, removal, or change of content, in a deliberate attempt to compromise the integrity of Wikipedia. Examples of typical vandalism are adding irrelevant obscenities and crude humor to a page, illegitimately blanking pages, and inserting obvious nonsense into a page. 

Wikipedia has an entire team and comprehensive guidelines for dealing with vandalism.
As of April 2014, there were 4,500,000 articles on Wikipedia. That's potentially 4,500,000 blank canvases for anyone with the inclination and an email address to put their mark on. Repeated transgressions will result in the user or their IP being banned from editing anything on Wikipedia. This is fine for Vandal A sitting at home trolling, but becomes a problem when an entire organisation's connection is blocked. They don't like to, but Wikipedia can block an entire IP range if the need arises. Jobs have been lost due to irresponsible Wikipedia edits (in Government, no less) — there are very real risks.

Here at Smoothwall, we've had more than one request for the ability to make Wikipedia read only in an effort to prevent this issue getting that far. Tomorrow this goes live and is in a similar vein to our previous work on Facebook and Twitter, albeit a little more niche. It's also not a blanket on/off switch, it's applicable the same way as any policy is — to whomever, whatever and whenever you like.