A Threat Model Canvas is a visual blueprint for understanding and managing cybersecurity risks. It's crucial because it prevents a reactive, "whack-a-mole" approach to security by providing a structured way to identify and prioritize potential threats. The canvas is divided into four quadrants: Assets (e.g., customer PII, financial data), Threat Actors (e.g., cyber-criminals, insiders), Attack Vectors (e.g., phishing, API abuse), and Controls (e.g., MFA, encryption). By scoring the likelihood and impact of identified risks, organizations can create a "RAG heat-map" (Red, Amber, Green) to prioritize mitigation efforts. This process typically involves a cross-functional workshop to brainstorm and identify the most critical risks for a 90-day mitigation backlog.