The article describes a system for culture-aware human-robot verbal interaction, that constitutes the basis for designing culturally-competent robots for health-care, i.e., robots able to autonomously re–configure their way of acting and speaking, when offering a service, to match the culture, customs, and etiquette of the person they are asstisting. The article shows how culture-aware verbal interaction is tightly related to cultural knowledge representation and acquisition, by describing the methodological and technological solutions adopted, and showing in details one of the preliminary experiments performed to design a culturally-competent robot