This study presents a grounded theory analysis of a case study in the banking industry with a view to showing the enabling role of ''Web services'' technology in information system development practices. The grounded theory analysis of the Cashier Management System development project at the Central Europe Bank (a pseudonym) shows that Web services technology is a key technological enabler for more agile forms of IS development, characterized by incremental analysis, requirements revision, requirements emerging in use and incremental implementation. In particular, an initial in-depth analysis phase, conducted in a traditional way, is then followed, during system development, by several iterative phases of requirements revision/addition, in fulfilment of emerging or previously unplanned user needs discovered along the way. Such system development practices, enabled by the Web services technology and influenced by a variety of contextual factors, cover a middle ground between methodical and amethodical development processes. This paper is the outcome of a joint effort from the two authors, who worked in close collaboration. This version is to be attributed to Maddalena Sorrentino for the last section, and to Francesco Virili for the rest of the paper, but Maddalena gave a substantial contribution in all the phases of research, elaboration and presentation of intermediate results. The initial idea originating this contribution was first proposed as an ECIS research in progress (Bello, Sorrentino and Virili 2002), to evolve at later stages and for different workshops, including (Virili and Sorrentino 2004) and (Sorrentino and Virili 2005).