This special issue explores how do we account for the sensitive, intimate ways in which our toolsets ‒ and our choices of these ‒ become the infrastructures that co-produce and co-constitute knowledge and meanings. Testing Against the World aimed at addressing, exploring, and making more explicit the following questions: What drives the choice of toolsets in empir­ical investigations? Why does contemporary research demand to be ‘grounded’ empirically? What professional, personal, and emo­tional attachments afford the selection of particular means of observation and translation? What do we expect from our tools? What do they expect of us? How are tools and technologies instrumen­talized? How have tools and research adapted or been forced to adapt to new empirical demands, and knowledge economies? What have such settings required us to assume, acquire, or impose? How do choices of instruments and tools pre-format worlds under investigation and authorize the creation of new worlds?