This session features insights from the SEEP Network's Systemic M&E Initiative, a practitioner led initiative supported by USAID and fhi360 that has been exploring innovative ways to monitor and evaluate interventions in market and financial systems. The session begins with an introduction to systems and characteristics of complex adaptive systems, seen by many as a promising model to improve the effectiveness of development initiatives when facing complex realities in market systems. This part of the session addresses questions such as: What exactly are systems? What are complex adaptive systems? What are the characteristics of such systems? Why are they relevant for inclusive market and financial development initiatives? The second part of the session introduces seven principles for monitoring and evaluating complex systems, and illustrates their application through project cases taken from international development initiatives. The session concludes with an outlook on planned activities by the Systemic M&E Initiative.