Through a discussion of the installation piece, The Trade / Oro por Baratijas, we address the theoretical issues behind the development of ecologically based compositional work. We discuss whether ecologically based music can be studied using linguistic tools. The concepts of potentiality and actuality are situated within the perspective of individual–environment interactions. A process that describes the relationship between an individual and his specific social context is proposed: the personal environment. Consistency is discussed in relation to environmental sound listening processes and ecological modelling work. The first part of the paper concludes by suggesting that form-creation is dynamically determined by a process of mutual adaptation between listener and environment. The second part focuses on compositional methods and contextual elements as they are used in The Trade. This work has been developed through a multilevel approach where visual and sonic materials stem from social and historical issues. The organisational processes of the sound piece are based on the micro-temporal and spectral properties suggested by the visual elements in the installation. The meso-temporal dynamic is organised through ecologically constrained events. The macro-structural shape and the sources used in the piece make reference to a specific historical context, i.e. the conquest of the American continent by the European armies during the first half of the sixteenth century.