Abstract: The present invention relates to an alignment apparatus for use in the construction of modular or prefabricated structures and a method for aligning the individual modules using the alignment apparatus. The apparatus is comprised of a first plate that has at least one pin positioned axially through the first plate, and an optional second plate having a pin-receiving hole. The modules are aligned by fastening the first plate to a first module and drilling a hole in the first and second modules to receive the pin. The modules are then joined together and are aligned by sliding the pin into the holes of the modules.