The paper, titled "Mapping by Observation: Building a User-Tailored Conducting System From Spontaneous Movements" presents a music interaction system based on the conductor-orchestra metaphor, where the orchestra is considered as an instrument controlled by the movements of the conductor. In the proposed system, the user can control tempo and dynamics and it adapts its mapping to the user by observing spontaneous conducting movements on top of a fixed music. In this respect, we analyze the tendency of people to anticipate or fall behind the beat and the gestures mapped to loudness. The system was evaluated with 24 participants in a discover-by-playing scenario.