The invention relates to: A medication delivery device and a method of making such a device. The object of the present invention is to provide a handy medication delivery device that may be easily adjusted to the different needs of a given user in different situations and to the different needs of different users, and which is economic from a production point of view. The problem is solved in that it comprises a basis module (1) and one or more replaceable modules (2, 3, 4, 5, 6), each of which is adapted to cooperate mechanically and / or electronically with the basis module to provide a specific function, and the basis module includes resources that are jointly used by the replaceable modules. This has the advantage of providing a rational concept for economically supplying high quality, mass-produced devices capable of being customized to individual users' needs for functionality by avoiding the duplication of key components. The invention may be used in injector type, medication pump type, inhaler or spray type devices for delivering a discrete dose or a continuous dose of a medication to a user.