Designers have a wide choice of concrete floor systems for their buildings. They can choose from three basic types available: in situ, precast or hybrid construction. A survey was conducted within the UK construction industry to investigate, in particular, the construction related factors influencing the choice of concrete floor systems. The data collected were subjected to frequency and severity index analyses, Kendall's concordance test and the chi-squared tests to produce a rank ordering of 12 construction related factors. Five factors were identified as being the most important, namely 'appropriateness of use', 'cost', 'constructability', 'speed' and 'health and safety'. These five factors reflect current industry emphasis, and therefore could be adopted as the principal criteria for evaluating and selecting concrete floor systems during the design stage. They could also be used as assessment criteria for developing future systems.Concrete Floors, Frame Construction, Selection Factors,