Abstract: An injector is disclosed for injecting an injectable substance into at least one of the epidermal tissue and the dermal tissue of a subject. The injector includes an outer housing and a control member disposed within the outer housing. A needle head, which is configured to support a plurality of needles, is operatively coupled to the control member. First means are provided in communication with the control member and are configured to be driven by the control member for converting a movement of the control member into a movement of the needle head along an injection direction and toward an injecting position of the needle head. Second means are configured to move the needle head in a direction having a component that is normal to the injection direction and absent movement of the outer housing relative to the skin of the subject.