Andrew Pickering's point of departure is the Strong Programme, but he has gradually distanced himself from crucial elements in it. Pickering describes science as generated by a mangle of practice. This metaphor accentuates the practical or instrumental aspect of science: Science is an attempt to achieve "machinic capture" of nature's agency by means of cultural tools and resources. In such capture, a stable interaction between physical nature and human resources is first established, e.g. in the form of a reliably running apparatus. Next, this apparatus is employed as an instrument of observation and measurement, to inform us about nature's ways. Capture is a dynamic process through which cultural resources are deployed in a creative and unpredictable manner. Hence, Pickering rejects the Strong Programme's ambition of explaining the development of science in terms of fixed and pre-existent causal factors. Pickering's explicitly relativistic attitude to scientific results generates problems of reflexivity, however, once his tenets are applied to his own work. In his later writings, Pickering has increasingly criticized the idea that human agency is radically different from the agency of things. He draws quite strong normative implications from this view, which are particularly clear in the field of technology studies into which he has gradually moved. He calls for human beings to respect the autonomy of nature as our equal when dealing with it in large-scale engineering projects. Thus, Pickering's thought has developed in the direction of a political, ecological agenda.