Drawing on social positioning theory and using dishwasher cooking as our running example, we examine how users arrive at alternative uses of already existing technological objects or what we will call “user innovations in function”. The first half of the paper provides an abstract account of three forms of structure: social structure, especially as represented by social positions; structures of cognition and action; and the structure of technological objects. The second half theorizes user innovations in function as emerging at the nexus of these different forms of structure, with a view to highlighting (1) the pre-reflective and reflective modes of agency involved; (2) how these relate to what we call “tinkering” and “reflection” in user innovation; and (3) the difference between “local” and “non-local” user innovations in function and their possible roots in tinkering or reflection.