Combinatorial test design (CTD) is an effective test planning technique that reveals faults that result from feature interactions in a system. The test space is manually modeled by a set of parameters, their respective values, and restrictions on the value combinations. A subset of the test space is then automatically constructed so that it covers all valid value combinations of every t parameters, where t is usually a user input. In many real-life testing problems, the relationships between the different test parameters are complex. Thus, precisely capturing them by restrictions in the CTD model might be a very challenging and time consuming task. From our experience, this is one of the main obstacles in applying CTD to a wide range of testing problems. In this paper, we introduce two new constructs to the CTD model, counters and value properties, that considerably reduce the complexity of the modeling task, allowing one to easily model testing problems that were practically impossible to model before. We demonstrate the impact of these constructs on two real-life case studies. © 2012 IEEE.