There are two main types of conservation a museum curator may perform on objects. The first type is to prevent any damage from happening to an object. The other type of conservation is the repair of damage that has already occured or the restoration of an object to a former, better condition.

Preventive Conservation
The Illinois State Museum practices preventive conservation-protecting objects by constantly monitoring the environments in which the collections are kept and controlling the temperature, light, and humidity levels. Some of the dangers objects face are:

• Exposure to light (especially ultraviolet light) can causes the chemical bonds in many materials to break down, making them weak or brittle. It may also cause colors to fade.
• Extreme heat or cold is also hard on objects, but frequent, large, or rapid changes in temperature are even worse. 
• High humidity can contribute to the spread of mold and mildew. Large changes in humidity can cause objects to shrink, swell, and crack. 
• Small particles of dirt and dust can scratch the surface of some objects or ruin their appearance. 
• Insects and other pests can eat or burrow through materials such as wood and cloth.  
• Objects may break because of improper handling or storage

Sometimes the Museum receives an object that would be excellent to exhibit, but that is not in very good condition. The Museum curator may ask for the assistance of a conservator. Conservators often have training in chemistry and are familiar with the ways certain materials react to various kinds of treatments. They can recommend the best treatment plan for an object in need of repair or restoration. 

See The Conservation of an Object: A Child's Wagon
to learn how an object can be restored to its earlier and better condition.