In political science, the debate of methodology is a long-standing one - qualitative work versus quantitative strategies, focusing on cases or on variables. Charles Ragin attempts to resolve this debate by offering a new approach that also aims to combine the advantages of both approaches. His solution lies in the application of Boolean algebra and its procedures on social science data. Instead of (for example) correlating variables, that often do not even measure the same phenomena, Ragin proposes to find threshold values and use binary variables. Thus, he hopes to solve the perennial problem of bad data and offers a way to do something like quantitative analysis of data that is derived from qualitative research - a way to circumvent the difficulties in finding comparable data for cross-national studies. Ragin then goes on to show other advantages of his Boolean approach. One lies in the fairly small set of possible operations in Boolean algebra, which nevertheless allow for a wide range of analyses. Plus, the binary nature of the approach, lends itself perfectly to computer analysis and the easy building of highly complex models. Although Ragin's book made quite an impact after its first publication there is only very little follow-up - only a handful of researchers are using his approach and the necessary software is not too easily available. But the approach is well worth considering, and possible extensions - for example using fuzzy logic - could lead to even more interesting possibilities. (Dies ist eine Amazon.de an der Uni-Studentenrezension.)