— This paper addresses high-level robot planning issues for an interactive cognitive robot that has to act in presence or in collaboration with a human partner. We describe a task planner called HATP (for Human Aware Task Planner). HATP is especially designed to handle a set of human-centered constraints in order to provide ”socially acceptable” plans that are oriented toward collaborative task achievement. We provide an overall description of HATP and discuss its main structure and algorithmic features.