The endeavor to naturalize the philosophy of biology brings the problem of agency to the forefront, along with renewed attention to the organism and organicism. In this article, we argue for a mutualist approach to agency that starts to unravel layers of this complex issue by focusing on perception and action at the core of all biological agency. The mutuality of animals and their surroundings is seen as distinct from the typical concepts of organism, preexisting environment, and their interactions. Mutuality (...) means a deep ontological and epistemological compatibility between the organism and its surround. We suggest that the concept of direct perception developed and empirically researched in the tradition of the ecological approach, launched by James J. Gibson, offers a promising path to approach agency within an ecological–mutuality framework. At the core of our definition of agency is the animal’s ability to self-initiate actions and activities. Animals are the source of their own actions and activities within the mutual, co-defining relation to their surround. The place of agency related to mutuality has not been elaborated sufficiently thus far, in either biology or ecological psychology. In this article, our goal is to argue for the necessity of placing agency into an ecological–mutuality framework and of further research in this direction in line with Marjorie Grene’s call to assimilate Gibson’s theory of knowledge into biology. (shrink)