The game I have been playing most lately is Prison Architect http://www.introversion.co.uk/prisonarchitect/

It's only a 2D game, but the simulation is quite gritty - none of the lala rainbows of later sims games. They take drugs, riot, and you even need a mortuary in the game (no grim reaper to tidy up - the bodies need carrying by guards). The aim is to build up reputation and funding by decreasing escapes etc and by rehabilitating prisoners so they don't reoffend.

The game is still in active development and there is a new alpha each month. But you do have to pay $30 for it - then all updates are free.

Sounds like fun - what's the colour scheme like? Gray, acid yellows, orange? I ask because you have to spend hours staring at the screen and I'm not sure I could cope with depressed colours.

Yeah, I know. Daft question.

Just went on Steam; there's a new update for Prison Architect today. Apparently the game allows modding now!

As for the colour scheme, it's quite realistic. Mostly subdued browns, greys, and such. And the prisoners wear the traditional orange uniforms.

Here's a link to it on Steam:
http://store.steampowered.com/app/233450

New update just came out; sounds pretty impressive. Prisoners now have reputations and behaviors based on these reputations, making the overall prison much harder to balance and maintain.

I'm just starting a new prison; can't wait to see how it develops!

I got this game, it's fun!

This game is good. I play it every once in a while. Built a high risk prison, and now a tazer going off is now routine.