Due to its dynamic and rapid development and due to a variety of academic disciplines and research communities contributing to information systems (IS) research, a broad variety of research approaches can be found. These approaches are often discussed as contrasting “paradigms”. Positivism and interpretivism are frequently accepted to be the most relevant paradigms (cf., for instance, Klein & Myers 1999; Lee 1991; Walsham 1995; Weber 2004). A further set of paradigms consists of behavioural science research (‘problem understanding paradigm’) and design science research (‘problem understanding paradigm’) which has been introduced in the IS literature and heavily adopted since (cf., for instance, Hevner et al. 2004; Jani 2001; March & Smith 1995). On top of this distinction, the critical research paradigm, including its logical complement, the non-critical paradigm, shaped the discussion of IS research philosophy for more than two decades (cf., for instance, Brooke 2002; Klein & Huynh 2004; Landry & Banville 1992; Mumford et al. 1985). Though it is essential to research theory and practice in the IS discipline to discuss the interconnections between these different sets of paradigms, such endeavour has not yet been undertaken. Some approaches address the interdependency between interpretivism and critical research. However, a holistic framework, also taking into account also behavioural and design science is still missing. Therefore, the aim of this paper is to provide an integrated discussion of these different sets of paradigms and to provide novel perspectives for IS research on how to deal with the apparent diversity of approaches. We will furthermore point out why this discussion is of great importance to IS research especially in Europe.