Social scientists have traditionally attempted to avoid extending strategies for acquiring experimental knowledge to the sphere of the social. Bruno Latour, however, has introduced a notion of the collective experiment, an experiment conducted by and with us all. In this short paper I seek to explore, by way of elucidating the talk of collective experiments, that Latour's notion has long since existed in the theory and practice of ecological design and restoration. Practitioners in ecological restoration projects find themselves in a (...) situation of double contingency, since neither do they know how nature will respond to their intervention nor is their interpretation of these responses already certain. Experimental practice in society then becomes the proceduralization of this contingency. (shrink)