Interior waterproofing and drainage
Interior systems can collect water near the footing and direct it to a sump. They can often be installed without excavating around the exterior of the home, which may make them practical for recurring perimeter seepage.
Exterior waterproofing
Exterior work exposes the foundation wall and can address wall defects, waterproofing layers, and footing drainage from outside. It is more disruptive but can be appropriate when the exterior wall itself needs treatment.
How to choose
Consider the water source, foundation condition, access, existing drainage, landscaping, project goals, and whether the symptoms are localized or widespread. A diagnosis should come before the method.