The subject of the 5th challenge proposed by the French Society of Operations Research and Decision Analysis (ROADEF) consists in scheduling technicians and interventions for telecommunications (www.g-scop.inpg.fr/ChallengeROADEF2007/). We present a Greedy Randomized Adaptive Search Procedure (GRASP) to solve this problem. The proposed method led us to 1st position in the Junior Category and to 4th position in the All Category of the Challenge.