A method cannot travel unchanged between cities simply because its questionnaire, map or spreadsheet remains identical. What appears to be a comparable variable may acquire another meaning when climate, urban form, political institutions, language, cultural habits or access conditions change. The opposite strategy, adapting everything to each location, risks producing a collection of compelling but mutually incommensurable descriptions. Comparative urban research consequently requires a decision about what must remain stable and what is permitted to move. ScalarArchitecture approaches comparison as controlled translation. Its proposed Scale Passport records the original research question, the scale at which evidence was produced, the methodological invariants, the locally adaptable elements, the transformations introduced and the equivalences that must not be claimed. Consider a comparison of public seating across two cities: a bench count may be straightforward, but its significance changes with shade, season, occupation, maintenance, informal use and the availability of alternatives. A common question about the conditions of staying can travel; a single indicator of what constitutes a successful place may not. The purpose is not to erase locality in search of a universal urban measure, nor to declare every place incomparable. It is to make the movement of the research instrument itself part of the record. Comparing two places means comparing not only their observed differences, but also the conditions under which those differences became legible. What survives the move is therefore less a fixed object than an explicit architecture of questions, relations and evidential limits.
