This is the most important thing in your park because if visitors don't feel safe, they will leave.
If there is an emergency, you can take charge of a helicopter or car, and rescue visitors or take out ravaging dinosaurs that have broken free of their confines and are wreaking havoc around the park. To assure the safety of your visitors, you need to set up the right types of fences (some dinosaurs need different fences), build ranger stations, and also set up other security measure such as cameras and avoidance beacons.
No one wants to visit a park where they could be eaten. You need to make sure your visitors are safe (though it's fun to sometimes watch carnivores devour the visitors).
You have been chosen by the eccentric billionaire and CEO of InGen John Hammond as the newest manager of Jurassic Park, a theme park featuring dinosaurs as its main attraction! InGen has provided you with a series of small islands to build up your park from, and has given you access to some of the richest fossil sites in the world! Make the park a safe and affordable holiday destination for the entire family! InGen is counting on you.