Project management under uncertainty: using flexible resource management to exploit schedule flexibility

Project management still faces a wide gap separating theory from practice, especially regarding the robustness of the generated project schedules facing the omnipresence of uncertainty. A new approach to deal with uncertainty is presented to explore slack that might exist in a given project schedule. We propose that renewable resources' capacity to perform work can be increased so that they can perform additional work in a time unit or can be decreased with the consequent reduction on the performed work. This possibility combined with the slack that some activities have in a specific schedule can be used to absorb deviations that might occur during a project's execution. When a critical activity is about to have its duration increased, slowing down other non-critical activities by putting their resources in a decreased work mode enables the activity to still be executed within time by using resources in an increased working mode. [Received: 14 February 2018; Revised: 2 January 2019; Revised: 8 June 2019; Accepted: 17 November 2019]