Looking for inspiration, Mark Webley, the game's designer, and Gary Carr, the lead artist, spent various hours walking around The Royal Surrey County Hospital in Guildford for ideas, but had no luck. They wrote to the hospital asking for a formal tour, but the hospital wanted a percentage of the game's profits, which they declined as they weren't sure how much the game would make.

The hospital Frimley Park, however, were open to offering them a tour and even allowed them to witness an operation, but the two were kicked out by the surgeon after they had been too noisy. They were even offered after a visit to the morgue, but declined as they already had the ideas they needed.

Pregnancy was supposed to be a condition in Theme Hospital. It is somewhat finished and can be restored with modding, but lacks graphics and is referred to as a "disease".