Bio Model Analyzer is a new biological modelling tool that illustrates signalling pathways and determines cellular stabilization. The tool represents a merging of perspectives from systems biology, formal methods, human computer interaction and design. At one level, Bio Model Analyzer is a sketching tool that enables users to draw out a biological system of interest (e.g. a genetic regulatory network) by dragging and dropping cells, their contents (DNA, proteins, etc.), extracellular components and relationships onto a simple canvas. At another level, Bio Model Analyzer’s analysis proves stabilization of biological systems, based upon formal methods that were developed for the specification and verification of properties in concurrent software systems.