A mixed integer linear programming model is presented for personnel planning of ground handling crews at Santiago International Airport in Chile. The model generates employee shift rosters for an entire month assuming heterogeneous workers (to reflect different skills demanded at specific times) that satisfy various constraints relating to legal restrictions, personnel demand, worker welfare criteria (fair shift assignments, elimination of undesirable shift patterns), and pre-existing work group assignments for achieving task synergies. Solutions are generated using a commercial solver, standardizing the shift assignment process and improving both personnel availability and worker welfare by objective standards compared to previous manual method solutions.