If you have a crack in your foundation that is from hairline up to 3/8 of an inch wide, the repair method is pretty common with a few exceptions in case you are also trying to enhance structural strength. The first step is cleaning the concrete so there is no paint, plaster, dirt or anything that would compromise the epoxy from adhering to the wall. Next a layer of epoxy is spread along the crack with plastic ports placed at appropriate distances where the filling material will be injected. After the epoxy dries either urethane or epoxy is injected starting at the bottom. After the material appears at the next port up the wall the lower port is capped and the injection continues like this all the way to the top of the wall. There are some exceptions but usually urethane is injected where a crack is leaking and epoxy is injected where structural strength is desired. In some cases it will be recommended to enhance wall strength by using carbon fiber ties or carbon fiber sheets over the crack to limit future wall movement. A single crack can usually be repaired in less than two hours and the cost is often in the $350 range. In most cases a crack repair will come with a warranty against future leaks.