Non-shrink grout is a hydraulic cement grout that produces a big volume that, when hardened under stipulated test conditions, is greater than or equal to the original installed volume; often used as a transfer medium between load-bearing members. 

Often sets rapidly
Usually a pre-mix product that needs only to be mixed with water
Includes ingredients to compensate against cement stone shrinkage
Use of shrinkage-compensating ingredients can result in volume increase over time.

Avoid high wind across the curing surface.
Avoid high temperatures during the cure.
Avoid common cement poisons, such as sulphates, acids, etc.
Failure to follow these precautions can adversely affect the quality of all cementitious products.