Paterno , F.Leonardi, A.2014-10-212014-10-2119941467-8659https://doi.org/10.1111/1467-8659.1330195Although tools for developing graphical user interfaces are becoming increasingly popular, they do not usually highlight precisely which key elements developers should take into account. This still entails considerable expertise in developing user interfaces. In this paper we present an approach to overcome these problems. Our approach is based on a model for interaction objects and a corresponding design space. This is supported by a toolkit where the available interaction objects are initially classified by their semantics whereas in most current toolkits they are investigated by their appearance. This facilitates designers and developers in identifying the interactors needed in order to obtain an Interactive System supporting user tasks.10.1111/1467-8659.1330195195-204