The preceding chapter introduced the motivation for further improving in automated synthesis methodologies for chaotic systems. Increasing the efficiency of synthesis, however, can be achieved if one uses higher abstraction levels to capture the behaviour of the analog systems. Behavioural modelling is seen as a promising solution that, combined with the appropriate synthesis tools, can be used to design multi-scrolls chaotic systems. Hence, this chapter first describes the basic concepts about nonlinear dynamical systems and the existing approaches to design chaotic systems as well as the applications of this class of systems. Afterwards, several important aspects in behavioural modelling are introduced. The steps performed during different design stages are represented by identifying the abstraction and description levels. Finally, the approaches for EDA of nonlinear dynamical systems are reviewed, and the interaction of four basic operations is discussed to introduce the definition of a synthesis methodology for analog designs based on behavioural modelling.