Counter-flowing jets are used as mixing devices in several engineering applications; for instance, effluent mixing in rivers and streams, mixing of fuel and air in turbojet engines etc. Although several experimental studies have been carried out on counter-flowing wall jets, these studies are limited to investigating the mean characteristics of the flow field. In the present study, a counter-flowing wall jet discharged into a main stream is computationally examined using three-dimensional, unsteady, Improved Delayed Detached Eddy Simulation. The results of the simulation are validated with experimental data and are presented with detailed discussions. The main flow parameters such as width of recirculation zone (h), penetration length of the jet (X_s) are determined. The shear layer and vortices in the flow are analyzed by examining the mean and instantaneous vorticity. The influence of the vortices on the flow field is discussed in detail.