This work deals with the modelling and control of the humanoid robot RH-1, a full scale humanoid prototype totally developed in the University Carlos III of Madrid and the only one existing in our country. The main objective is to develop an advanced control system that allows cooperation tasks to be carried out semi-autonomously between humanoid robots and humans in real working environments. The kinematic model and a simplification of the dynamic model of the robot are presented in this paper, together with a control strategy for the stabilization of the system during the walking and collaborative actions. Several simulation and experimental results are also given along the paper to illustrate the work.