Because differential settlement is often caused by excess moisture in the soil around the foundation, you can go a long way toward preventing problems by simply controlling groundwater around the foundation. Here are some ways to do that:
If necessary, regrade the yard around your home so that it slopes away from the foundation. This will prevent water from draining toward the foundation and soaking into the soil.
Use downspout extensions to carry runoff away from the foundation before being released.
Consider relocating any water-hungry vegetation planted next to the house.
Install a drain tile system, either exterior or interior. This will help prevent excess moisture from building up in the ground around the foundation.