::an O/R-mapper generates the DAL? Only a bad one. There is actually never any need to GENERATE a DAL. An O/R mapper will normally include a generc dal that configures itself using schema information available (which is also possible without an O/R mapper - I really wonder what people consider "good programming" in writing the repetiticve DAL code themselves). An O/R mapper basically means your BLL contains object, and you dont have to deal with anything below the objects (like persistence, SQL etc.). This is actually THE way to write applications, and a great timesaver - it can reduce your code-count by about 30% upwards.