We present a new variant of the multi-skill project scheduling problem that uses the concept of partial preemption. The variant of the problem under study is then called Multi-Skill Project Scheduling Problem with Partial Preemption (MSPSP-PP). To the best of our knowledge, this problem has not been studied yet in the scientific literature. The objective is to find a feasible schedule that minimises the total duration of the project. The problem is strongly NP-hard. We propose different formulations for the MSPSP-PP using Mixed-Integer/Linear Programming and Constraint Programming.