This document summarizes a guest lecture about intervening in social systems through business model disruption. The key points made are: 1. Systems are made up of interlocking business models, and systems change when business models change. 2. Disruption involves fundamentally changing business models, such as moving from ownership to sharing, disintermediating processes, unlocking inventory, commoditizing value sources, and changing capital risk sequences. 3. Characteristics of disruptions are that they initially provide lower quality but good enough products at lower margins but higher volumes, and ultimately grow the market by serving non-consumers.