Complexity Machine1 isa softwareapplication developed by theauthor asa Master ofArchitecturethesisproject at theUniversity ofMinnesota. The software acts as a platform for exploring three dimensional form produced via behavioral simulation. Specifically, the behaviors are modeled on emergent group dynamics found commonly in nature such as flocking, chasing, and evading. Though various commercial softwares and numerous small-scale architectural projects exist in this area, Complexity Machine 1 is intended as a freely available and generic platform for exploring the formal implications of these emergent behaviors. The simulated behaviors are governed by a variety of parameters and a set of eight simple rules. Formal results are influenced by these parameters and rules; along with scale, color, and geometric settings. The flexibility of the software allows users to investigate a vast array of potential forms, adjust settings in real time, and export the results for further manipulation. Complexity Machine 1 continues to be refined and improved towards the goal of providing an easy to use platform to designers for exploring forms that emerge from complex group behavior.