Cluster analysis according to the activities IS practitioners perform shows that IS practitioners can be broadly categorized into two groups, generalists and specialists: generalists allocate their work time relatively evenly across the activities while specialists allocate more time on some specific activities than on other activities. Empirical findings also show that generalists and specialists are required to possess different configurations of IS knowledge and skills respectively to do their work successfully and that they possess different configurations of IS knowledge and skills. Empirical findings reveal that specialists change the activities they do mainly as their carrier evolves while generalists do not.