When multiple calls occur simultaneously or within a short period of time, communities rely on a system known as mutual aid. Mutual aid allows one community to assist another. When both Grafton ambulances are busy or a major incident occurs, such as a mass casualty or structure fire, additional resources are requested from neighboring communities. Most fire departments nationwide (including large cities like Chicago and Milwaukee) send and receive mutual aid from other area departments on a regular basis. Resources and staffing vary by department, however they all have limits.
Although it is rare to respond outside of Ozaukee County, Grafton has provided resources to other departments as far away as Kenosha County, Waukesha County and Racine County for major incidents in recent years.