Between the 1960s and early-1980s the museum sector in the United Kingdom (UK) was rapidly professionalised and systematised. A crucial moment in this transition was the creation in 1967 of the Information Retrieval Group of the Museums Association (IRGMA), and the subsequent launch of its system for the machine encoding and communication of museum catalogue records. The rise of IRGMA marked an inflection point in museological practice and the normalisation of computerised work within the UK museum profession, a moment when the desire for a ‘layman's guide to the scheme’ began to give way to new professional personas and forms of documentary labour. This article asks how cultures of museology and professional labour shifted in response to IRGMA. It argues that between the late 1960s and mid-1980s both the implementation of and the debate around computerised cataloguing disrupted the function of UK museums and how museum professionals imagined their labour. And by tracing the emergence of these cultures and their intersections with professional identity and labour practices, this article seeks to tease out the ways museum history can resonate with wider narratives of labour, expertise and technological innovation in contemporary British history.